Substrate processing apparatus

ABSTRACT

A supply flow passage branches into a plurality of upstream flow passages. The plurality of upstream flow passages include a branching upstream flow passage that branches into a plurality of downstream flow passages. A plurality of discharge ports are respectively disposed at a plurality of positions differing in distance from a rotational axis and discharge processing liquids, supplied via the plurality of upstream flow passages, toward an upper surface of a substrate held by a substrate holding unit.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a substrate processing apparatus whichprocesses a substrate. Substrates to be processed include, for example,semiconductor wafers, liquid crystal display device substrates, plasmadisplay substrates, FED (Field Emission Display) substrates, opticaldisk substrates, magnetic disk substrates, magneto-optical disksubstrates, photomask substrates, ceramic substrates, and photovoltaiccell substrates.

2. Description of Related Art

Japanese Patent Application Publication No. 2006-344907 discloses asingle substrate processing type substrate processing apparatus thatprocesses a substrate, such as a semiconductor wafer, etc., one by one.The substrate processing apparatus includes a spin chuck that rotatesthe substrate while holding the substrate horizontally and a nozzle thatdischarges a processing liquid of higher temperature than, roomtemperature toward an upper surface central portion of the substrateheld by the spin chuck. The high temperature processing liquiddischarged from the nozzle lands on the upper surface central portion ofthe substrate and thereafter flows outward along the upper surface ofthe rotating substrate. The high temperature processing liquid isthereby supplied to an entire upper surface of the substrate.

The processing liquid that lands on the upper surface central portion ofthe rotating substrate flows from a central portion to a peripheral edgeportion along the upper surface of the substrate. In this process, thetemperature of the processing liquid decreases gradually. Temperatureuniformity is thus decreased and processing uniformity is degraded.Although increasing a flow rate of the processing liquid discharged fromthe nozzle reduces the time taken for the processing liquid to reach theupper surface peripheral edge portion of the substrate and alleviatesthe lowering of the temperature of the processing liquid, in this case,the consumption amount of the processing liquid increases.

SUMMARY OF THE INVENTION

A preferred embodiment of the present invention provides a substrateprocessing apparatus including a substrate holding unit rotating asubstrate around a vertical rotational axis passing through a centralportion of the substrate while holding the substrate horizontally, and aprocessing liquid supplying system supplying a processing liquid to thesubstrate held by the substrate holding unit.

The processing liquid supplying system includes a supply flow passage, aplurality of upstream flow passages, a plurality of downstream flowpassages, and a plurality of discharge ports. The supply flow passageguides the processing liquid toward the plurality of upstream flowpassages. The plurality of upstream flow passages branch from the supplyflow passage and guide the processing liquids, supplied from the supplyflow passage, toward the plurality of discharge ports. The plurality ofdischarge ports include a main discharge port, discharging theprocessing liquid toward an upper surface central portion of thesubstrate, and a plurality of auxiliary discharge ports, disposed awayfrom the upper surface central portion, differing in distance from therotational axis, and respectively discharging the processing liquidstoward a plurality of positions within an upper surface of thesubstrate, and are respectively disposed at a plurality of positionsdiffering in distance from the rotational axis and discharge theprocessing liquids, supplied via the plurality of upstream flowpassages, toward the upper surface of the substrate held by thesubstrate holding unit. The plurality of upstream flow passages includea main upstream flow passage connected to the main discharge port and aplurality of auxiliary upstream flow passages connected to the pluralityof auxiliary discharge ports via the plurality of downstream flowpassages. Each of the plurality of the auxiliary upstream flow passagesis a branching upstream flow passage that branches into a plurality ofthe downstream flow passages and each auxiliary discharge port isrespectively provided according to each downstream flow passage.

With this arrangement, the supply flow passage guiding the processingliquid branches into the plurality of upstream flow passages. The numberof discharge ports can thereby be increased. Further, the branchingupstream flow passages branching into the plurality of downstream flowpassages are included in the plurality of upstream flow passages and thenumber of discharge ports can thus be increased further. The processingliquid flowing through the supply flow passage is supplied to thedischarge ports from the upstream flow passages or the downstream flowpassages and discharged toward the upper surface of the substrate thatrotates around the rotational axis. The plurality of discharge ports arerespectively disposed at the plurality of positions differing indistance from the rotational axis. Temperature uniformity of theprocessing liquid on the substrate can thus be increased in comparisonto a case where the processing liquid is discharged from just a singledischarge port. Processing uniformity can thereby be increased whilereducing the consumption amount of the processing liquid.

In a case where processing liquids are discharged from a plurality ofdischarge ports toward a plurality of positions that are separated in aradial direction, it is important, in terms of improvement of processinguniformity, that processing liquids of the same quality are supplied tothe respective portions of the substrate. If a tank and a filter, etc.,are provided for each discharge port, the processing liquid supplied toa certain discharge port may differ in quality from the processingliquid supplied to another discharge port. On the other hand, with thepresent preferred embodiment, the supply flow passage is branched sothat the processing liquids supplied from the same flow passage (supplyflow passage) are discharged from the respective discharge ports.Processing liquids of the same quality can thereby be discharged fromthe respective discharge ports. Further, in comparison to an arrangementwhere a tank and a filter, etc., are provided according to eachdischarge port, the number of parts can be reduced and maintenance workcan be simplified.

In the present preferred embodiment, at least one of the followingfeatures may be added to the above substrate processing apparatus.

The processing liquid supplying system further includes an upstreamheater and a plurality of downstream heaters, the upstream heater heatsthe processing liquid, supplied to the supply flow passage, at anupstream temperature, and the plurality of downstream heaters arerespectively connected to the plurality of auxiliary upstream flowpassages and heat the processing liquids, flowing through the pluralityof auxiliary upstream flow passages, at downstream temperatures higherthan the upstream temperature.

If the processing liquid is higher in temperature than the substrate,the heat of the processing liquid is transferred from the processingliquid to the substrate. Also, since the processing liquid rotatestogether with the substrate, the processing liquid on the substrateflows outward along the upper surface of the substrate while beingcooled by air. Circumferential speeds of respective portions of thesubstrate increase as the distance from the rotational axis increases.The processing liquid on the substrate is cooled more readily when thecircumferential speed is higher. Also, if it is supposed that the uppersurface of the substrate can be divided into a plurality of circularannular regions at equal intervals in a radial direction, the respectiveregions increase in area as the distance from the rotational axisincreases. When the surface area increases, heat to be transferred fromthe processing liquid to a circular annular region increases. Thereforeif the temperatures of the processing liquids discharged from thedischarge ports are all the same, sufficient temperature uniformity maynot be obtained.

With this arrangement, the processing liquids that have been heated atthe downstream temperatures higher than the upstream temperature by thedownstream heaters are supplied to the plurality of auxiliary dischargeports from the plurality of auxiliary upstream flow passages and aredischarged from the discharge ports. That is, whereas the processingliquid of the upstream temperature is discharged from the main dischargeport, the processing liquid of higher temperature than the upstreamtemperature is discharged from each of the plurality of auxiliarydischarge ports. Since the temperatures of the processing liquidssupplied to the upper surface of the substrate increase stepwise as thedistance from the rotational axis increases, the temperature uniformityof the processing liquid on the substrate can thus be increased incomparison to a case where the processing liquid of the same temperatureis discharged from each discharge port. The processing uniformity canthereby be increased while reducing the consumption amount of theprocessing liquid.

The processing liquid supplying system further includes a plurality ofreturn flow passages, a plurality of downstream heaters, and adownstream switching unit, the plurality of return flow passages arerespectively connected to the plurality of auxiliary upstream flowpassages at positions further upstream than the plurality of auxiliarydischarge ports, the plurality of downstream heaters are respectivelyconnected to the plurality of auxiliary upstream flow passages atpositions further upstream than the connection positions of the returnflow passages and the auxiliary upstream flow passages and heat liquidsflowing through the plurality of auxiliary upstream flow passages, andthe downstream switching unit switches to any of a plurality of statesincluding a discharging state, in which the liquid supplied to theplurality of upstream flow passages from the supply flow passage issupplied to the plurality of discharge ports, and a discharge stoppagestate, in which the liquid supplied to the plurality of upstream flowpassages from the supply flow passage is supplied to the plurality ofreturn flow passages.

The temperature of the processing liquid may have a large influence onthe processing of the substrate. If the downstream heaters are stoppedduring discharge stoppage, it will take time for the temperatures of theprocessing liquids, heated by the downstream heaters, to stabilize atthe intended temperatures when operation of the downstream heaters isrestarted. The discharges of the processing liquids thus cannot berestarted immediately and throughput (number of substrates processed perunit time) decreases. It is therefore preferable for the liquids to beheated by the downstream heaters even during discharge stoppage.

With this arrangement, during discharge stoppage, the liquids aresupplied to the upstream flow passages and heated by the downstreamheaters. The liquids heated by the downstream heaters are not dischargedfrom the plurality of discharge ports but flow from the upstream flowpassages into the return flow passages. A state where the temperaturesof the downstream heaters are stable can thus be maintained even duringdischarge stoppage. The discharge of the processing liquid can thus berestarted immediately.

The substrate processing apparatus further includes a chamber housingthe substrate held by the substrate holding unit and the branchingupstream flow passages branch into the plurality of downstream flowpassages inside the chamber.

With this arrangement, upstream ends of the plurality of downstream flowpassages are disposed inside the chamber. The branching upstream flowpassages branch into the plurality of downstream flow passages insidethe chamber. Each downstream flow passage can thus be reduced in length(length in a direction in which the liquid flows) in comparison to acase where the branching upstream flow passages are branched outside thechamber. Temperature decrease of the processing liquid due to heattransfer from the processing liquid to each downstream flow passage canthereby be suppressed.

The processing liquid supplying system further includes a first nozzleand a second nozzle, the plurality of discharge ports include a firstdischarge port, disposed in the first nozzle, and a second dischargeport, disposed in the second nozzle, and are aligned in a plan view in aradial direction orthogonal to the rotational axis, the first nozzleincludes a first arm portion extending in a horizontal longitudinaldirection and a first tip portion extending downward from a tip of thefirst arm portion, the second nozzle includes a second arm portionextending in the longitudinal direction and a second tip portionextending downward from a tip of the second arm portion, the first armportion and the second arm portion are aligned in a horizontal alignmentdirection orthogonal to the longitudinal direction, and the tip of thefirst arm portion and the tip of the second arm portion are separated inthe longitudinal direction in a plan view such that the tip of the firstarm portion is positioned at the rotational axis side.

With this arrangement, the plurality of discharge ports are aligned in aplan view in the radial direction. When a plurality of nozzles of thesame length are aligned in the horizontal direction orthogonal to thelongitudinal direction so that the plurality of discharge ports arealigned in a plan view in the radial direction, an entirety of theplurality of nozzles increases in width (see FIG. 9). When a pluralityof nozzles of different lengths are aligned in a vertical direction sothat the plurality of discharge ports are aligned in a plan view in theradial direction, the entirety of the plurality of nozzles increases inheight (see FIG. 10A and FIG. 10B).

On the other hand, when the first arm portion and the second arm portionare aligned in the horizontal alignment direction orthogonal to thelongitudinal direction and the tip of the first arm portion and the tipof the second arm portion are shifted in the longitudinal direction in aplan view such that the tip of the first arm portion is positioned atthe rotational axis side, the plurality of discharge ports can bealigned in the radial direction in a plan view while suppressing boththe width and the height of the entirety of the plurality of nozzles(see FIG. 4). The plurality of nozzles and associated members, such as astandby pot, etc., can thereby be made compact.

The plurality of discharge ports include an oblique discharge port thatdischarges the processing liquid in a discharge direction that isobliquely inclined with respect to the upper surface of the substrate,held by the substrate holding unit, so as to approach the rotationalaxis as the upper surface of the substrate is approached.

With this arrangement, the oblique discharge port, which is included inthe plurality of discharge ports, discharges the processing liquid inthe discharge direction that is inclined inwardly with respect to theupper surface of the substrate. The discharged processing liquid haskinetic energy of a direction directed toward the rotational axis andtherefore flows along the upper surface of the substrate toward therotational axis. Thereafter, the processing liquid flows outward alongthe upper surface of the substrate due to a centrifugal force generatedby the rotation of the substrate and is expelled from the upper surfaceof the substrate. A retention time of the processing liquid on thesubstrate is thus increased in comparison to a case where the processingliquid is discharged in a direction perpendicular to the upper surfaceof the substrate or in a case where it is discharged in a direction thatis outwardly inclined with respect to the upper surface of thesubstrate. The processing liquid can thus be used efficiently and theconsumption amount of the processing liquid can be reduced.

The substrate processing apparatus further includes a controllercontrolling the processing liquid supplying system, the processingliquid supplying system further includes a plurality of dischargevalves, the plurality of discharge ports include a first discharge portand a second discharge port disposed further from the rotational axisthan the first discharge port, the plurality of upstream flow passagesinclude a first upstream flow passage guiding the processing liquidtoward the first discharge port and a second upstream flow passageguiding the processing liquid toward the second discharge port, theplurality of discharge valves include a first discharge valve openingand closing the first upstream flow passage and a second discharge valveopening and closing the second upstream flow passage, and the controlleropens the first discharge valve and the second discharge valve so that atime during which the second discharge valve is open is longer than atime during which the first discharge valve is open and thereaftercloses the first discharge valve and the second discharge valve.

The controller may successively open the first discharge valve and thesecond discharge valve in the order of the second discharge valve andthe first discharge valve and thereafter close the first discharge valveand the second discharge valve at the same time. The controller may openthe first discharge valve and the second discharge valve at the sametime and thereafter successively close the first discharge valve and thesecond discharge valve in the order of the first discharge valve and thesecond discharge valve. The controller may successively open the firstdischarge valve and the second discharge valve in the order of thesecond discharge valve and the first discharge valve and thereaftersuccessively close the first discharge valve and the second dischargevalve in the order of the first discharge valve and the second dischargevalve.

With this arrangement, the first discharge port is disposed furtherinward than the second discharge port. The processing liquid dischargedfrom the first discharge port lands on a first liquid landing positionwithin the upper surface of the substrate. The processing liquiddischarged from the second discharge port lands on a second liquidlanding position within the upper surface of the substrate. The secondliquid landing position is a position further outward than the firstliquid landing position. The discharges of processing liquids from thefirst discharge port and the second discharge port are controlled by thecontroller.

For example, the controller starts the discharge of the processingliquid from the second discharge port and thereafter starts thedischarge of the processing liquid from the first discharge port.Thereafter, the controller ends the discharge of the processing liquidfrom the first discharge port and the discharge of the processing liquidfrom the second discharge port at the same time. A processing liquidsupplying time for a region further to the outer side than the secondliquid landing position is thus longer than a processing liquidsupplying time for a region further to the inner side than the secondliquid landing position.

If the processing liquid is discharged from just a single dischargeport, an etching rate (etching amount of the substrate per unit time)tends to decrease with distance away from a central portion of thesubstrate. Therefore, by increasing the processing liquid supplying timewith distance away from the central portion of the substrate, theetching amounts at positions besides the central portion of thesubstrate can be increased. The processing uniformity can thereby beincreased.

The processing liquid supplying system further includes a nozzle movingunit and a discharge position adjusting unit, the nozzle moving unitmoves the plurality of discharge ports and the discharge positionadjusting unit horizontally between a processing position, at which theplurality of discharge ports and the substrate overlap in a plan view,and a standby position, at which the plurality of discharge ports andthe substrate do not overlap in a plan view, and the discharge positionadjusting unit moves the plurality of discharge ports in a horizontaladjusting direction differing from a direction of movement of theplurality of discharge ports by the nozzle moving unit.

With this arrangement, the nozzle moving unit moves the plurality ofdischarge ports and the discharge position adjusting unit horizontallybetween the processing position and the standby positions. At theprocessing position, the plurality of discharge ports are respectivelydisposed at the plurality of positions differing in distance from therotational axis. When the discharge position adjusting unit moves theplurality of discharge ports in the adjusting direction, all of thedischarge ports are either moved closer to or further away from therotational axis and the liquid landing positions of the processingliquids with respect to the upper surface of the substrate are moved. Anetching profile (cross-sectional shape of the upper surface of thesubstrate after etching) can be adjusted by making the dischargeposition adjusting unit move the plurality of discharge ports.

Another preferred embodiment of the present invention provides asubstrate processing apparatus including a substrate holding unitrotating a substrate around a vertical rotational axis passing through acentral portion of the substrate while holding the substratehorizontally, and a processing liquid supplying system supplying aprocessing liquid to the substrate held by the substrate holding unit.

The processing liquid supplying system includes a supply flow passage, aplurality of upstream flow passages, a plurality of discharge ports, anda nozzle moving unit. The supply flow passage guides the processingliquid toward the plurality of upstream flow passages. The plurality ofupstream flow passages branch from the supply flow passage and guide theprocessing liquids, supplied from the supply flow passage, toward theplurality of discharge ports. The plurality of discharge ports include amain discharge port, discharging the processing liquid toward an uppersurface central portion of the substrate, and a plurality of auxiliarydischarge ports, disposed away from the upper surface central portion,differing in distance from the rotational axis, and respectivelydischarging the processing liquids toward a plurality of positionswithin an upper surface of the substrate, and are respectively disposedat a plurality of positions differing in distance from the rotationalaxis and discharge the processing liquids, supplied via the plurality ofupstream flow passages, toward the upper surface of the substrate heldby the substrate holding unit. The plurality of upstream flow passagesinclude a main upstream flow passage connected to the main dischargeport and a plurality of auxiliary upstream flow passages connected tothe plurality of auxiliary discharge ports. The nozzle moving unitswings the plurality of discharge ports to change the distances from therotational axis to the plurality of discharge ports in a state where thesubstrate holding unit is rotating the substrate and the plurality ofdischarge ports are discharging the processing liquids toward the uppersurface of the substrate. The swinging of the plurality of dischargeports may be a reciprocal movement or a zigzag movement.

With this arrangement, the supply flow passage guiding the processingliquid branches into the plurality of upstream flow passages. The numberof discharge ports can thereby be increased. The processing liquidflowing through the supply flow passage is supplied to the dischargeports via the upstream flow passages and discharged toward the uppersurface of the substrate that rotates around the rotational axis. Theplurality of discharge ports are respectively disposed at the pluralityof positions differing in distance from the rotational axis. Thetemperature uniformity of the processing liquid on the substrate canthus be increased in comparison to a case where the processing liquid isdischarged from just a single discharge port. The processing uniformitycan thereby be increased while reducing the consumption amount of theprocessing liquid.

Further with the present arrangement, the nozzle moving unit swings theplurality of discharge ports in the state where the substrate isrotating and the plurality of discharge ports are discharging theprocessing liquids. The distances from the rotational axis to therespective discharge ports are thereby changed. The processing liquidsdischarged from the plurality of discharge ports land on the pluralityof liquid landing positions within the upper surface of the substrate.The etching amount of the substrate is greatest at each liquid landingposition and decreases with distance away from the liquid landingposition. The plurality of discharge ports are moved horizontally andthe plurality of liquid landing positions are moved within the uppersurface of the substrate accordingly. The processing uniformity canthereby be increased in comparison to a case where the plurality ofdischarge ports are not moved.

In the present preferred embodiment, at least one of the followingfeatures may be added to the substrate processing apparatus.

The processing liquid supplying system further includes a plurality ofdownstream flow passages, each of the plurality of auxiliary upstreamflow passages is a branching upstream flow passage that branches into aplurality of the downstream flow passages, and each auxiliary dischargeport is respectively provided according to each downstream flow passage.

With this arrangement, the flow passages supplying the processingliquids to the plurality of discharge ports are branched into multiplestages. That is, the supply flow passage branches into the plurality ofupstream flow passages (first branching) and the branching upstream flowpassages, included among the plurality of upstream flow passages, branchinto the plurality of downstream flow passages (second branching). Thenumber of discharge ports can thus be increased in comparison to a casewhere the branching upstream flow passages are not included among theplurality of upstream flow passages. The temperature uniformity of theprocessing liquid on the substrate can thereby be increased further andthe processing uniformity can be increased further.

The substrate processing apparatus further includes a chamber housingthe substrate held by the substrate holding unit and the branchingupstream flow passages branch into the plurality of downstream flowpassages inside the chamber.

With this arrangement, upstream ends of the plurality of downstream flowpassages are disposed inside the chamber. The branching upstream flowpassages branch into the plurality of downstream flow passages insidethe chamber. Each downstream flow passage can thus be reduced in length(length in a direction in which the liquid flows) in comparison to acase where the branching upstream flow passages are branched outside thechamber. Temperature decrease of the processing liquid due to heattransfer from the processing liquid to each downstream flow passage canthereby be suppressed.

The processing liquid supplying system further includes an upstreamheater and a plurality of downstream heaters, the upstream heater heatsthe processing liquid, supplied to the supply flow passage, at anupstream temperature, and the plurality of downstream heaters arerespectively connected to the plurality of auxiliary upstream flowpassages at positions further upstream than the plurality of auxiliarydischarge ports and heat the processing liquids flowing through theplurality of auxiliary upstream flow passages, at downstreamtemperatures higher than the upstream temperature.

With this arrangement, the processing liquids that have been heated atthe downstream temperatures higher than the upstream temperature by thedownstream heaters are supplied to the plurality of auxiliary dischargeports from the plurality of auxiliary upstream flow passages and aredischarged from the discharge ports. That is, whereas the processingliquid of the upstream temperature is discharged from the main dischargeport, the processing liquid of higher temperature than the upstreamtemperature is discharged from each auxiliary discharge port. Thetemperatures of the processing liquids supplied to the upper surface ofthe substrate thus increase stepwise with distance away from therotational axis and the temperature uniformity of the processing liquidon the substrate can thus be increased in comparison to a case where theprocessing liquid of the same temperature is discharged from eachdischarge port. The processing uniformity can thus be increased whilereducing the consumption amount of the processing liquid.

The processing liquid supplying system further includes a plurality ofreturn flow passages, a plurality of downstream heaters, and adownstream switching unit, the plurality of return flow passages arerespectively connected to the plurality of auxiliary upstream flowpassages at positions further upstream than the plurality of auxiliarydischarge ports, the plurality of downstream heaters are respectivelyconnected to the plurality of auxiliary upstream flow passages atpositions further upstream than the connection positions of the returnflow passages and the auxiliary upstream flow passages and heat theprocessing liquids flowing through the plurality of auxiliary upstreamflow passages, and the downstream switching unit switches to any of aplurality of states including a discharging state, in which theprocessing liquid supplied to the plurality of upstream flow passagesfrom the supply flow passage is supplied to the plurality of dischargeports, and a discharge stoppage state, in which the processing liquidsupplied to the plurality of upstream flow passages from the supply flowpassage is supplied to the plurality of return flow passages.

With this arrangement, during discharge stoppage, the processing liquidis supplied to the upstream flow passage and heated by the downstreamheaters. The processing liquids heated by the downstream heaters are notdischarged from the plurality of discharge ports but flow from theupstream flow passages into the return flow passages. A state where thetemperatures of the downstream heaters are stable can thus be maintainedeven during discharge stoppage. The discharge of the processing liquidcan thus be restarted immediately.

The processing liquid supplying system further includes a first nozzleand a second nozzle, the plurality of discharge ports include a firstdischarge port, disposed in the first nozzle, and a second dischargeport, disposed in the second nozzle, and are aligned in a plan view in aradial direction orthogonal to the rotational axis, the first nozzleincludes a first arm portion extending in a horizontal longitudinaldirection and a first tip portion extending downward from a tip of thefirst arm portion, the second nozzle includes a second arm portionextending in the longitudinal direction and a second tip portionextending downward from a tip of the second arm portion, the first armportion and the second arm portion are aligned in a horizontal alignmentdirection orthogonal to the longitudinal direction, and the tip of thefirst arm portion and the tip of the second arm portion are separated inthe longitudinal direction in a plan view such that the tip of the firstarm portion is positioned at the rotational axis side.

With this arrangement, the first discharge port and the second dischargeport are aligned in a plan view in the radial direction. When aplurality of nozzles of the same length are aligned in the horizontaldirection orthogonal to the longitudinal direction so that the pluralityof discharge ports are aligned in a plan view in the radial direction,the entirety of the plurality of nozzles increases in width (see FIG.9). When a plurality of nozzles of different lengths are aligned in avertical direction so that the plurality of discharge ports are alignedin a plan view in the radial direction, the entirety of the plurality ofnozzles increases in height (see FIG. 10A and FIG. 10B).

On the other hand, when the first arm portion and the second arm portionare aligned in the horizontal alignment direction orthogonal to thelongitudinal direction and the tip of the first arm portion and the tipof the second arm portion are shifted in the longitudinal direction in aplan view such that the tip of the first arm portion is positioned atthe rotational axis side, the plurality of discharge ports can bealigned in the radial direction in a plan view while suppressing boththe width and the height of the entirety of the plurality of nozzles(see FIG. 4). The plurality of nozzles and associated members, such as astandby pot, etc., can thereby be made compact.

Another preferred embodiment of the present invention provides asubstrate processing apparatus including a substrate holding unitrotating a substrate around a vertical rotational axis passing through acentral portion of the substrate while holding the substratehorizontally, a processing liquid supplying system supplying aprocessing liquid to the substrate held by the substrate holding unit,and a gas supplying unit supplying a gas to the substrate held by thesubstrate holding unit.

The processing liquid supplying system includes a supply flow passage, aplurality of upstream flow passages, and a plurality of discharge ports.The gas supplying unit includes a plurality of gas discharge ports. Thesupply flow passage guides the processing liquid toward the plurality ofupstream flow passages. The plurality of upstream flow passages branchfrom the supply flow passage and guide the processing liquids, suppliedfrom the supply flow passage, toward the plurality of discharge ports.The plurality of discharge ports include a main discharge port,discharging the processing liquid toward an upper surface centralportion of the substrate, and a plurality of auxiliary discharge ports,disposed away from the upper surface central portion, differing indistance from the rotational axis, and respectively discharging theprocessing liquids toward a plurality of positions within an uppersurface of the substrate, and are respectively disposed at a pluralityof positions differing in distance from the rotational axis anddischarge the processing liquids, supplied via the plurality of upstreamflow passages, toward the upper surface of the substrate held by thesubstrate holding unit. The plurality of upstream flow passages includea main upstream flow passage connected to the main discharge port and aplurality of auxiliary upstream flow passages connected to the pluralityof auxiliary discharge ports. The plurality of gas discharge ports arerespectively disposed at a plurality of positions differing in distancefrom the rotational axis and discharge a gas of temperature higher thanroom temperature toward the upper surface of the substrate held by thesubstrate holding unit. The gas may be an inert gas, such as nitrogengas, etc., clean air filtered by a filter, or a gas besides the above.The temperature of the gas is preferably lower than a boiling point ofthe processing liquid on the substrate.

With this arrangement, the supply flow passage guiding the processingliquid branches into the plurality of upstream flow passages. The numberof discharge ports can thereby be increased. The processing liquidflowing through the supply flow passage is supplied to the dischargeports via the upstream flow passages and discharged toward the uppersurface of the substrate that rotates around the rotational axis. Theplurality of discharge ports are respectively disposed at the pluralityof positions differing in distance from the rotational axis. Thetemperature uniformity of the processing liquid on the substrate canthus be increased in comparison to a case where the processing liquid isdischarged from just a single discharge port. The processing uniformitycan thereby be increased while reducing the consumption amount of theprocessing liquid.

Further with the present arrangement, the gas discharge ports dischargethe gas toward blowing-on positions within the upper surface of thesubstrate in a state where the upper surface of the substrate is coveredwith a liquid film of the processing liquid. A discharge pressure of thegas is a pressure such that the blowing-on positions do not becomeexposed from the processing liquid. The discharged gas is a hightemperature gas of higher temperature than room temperature. Therefore,by the supplying of the gas, an improvement can be made in regard totemperature decrease of the processing liquid on the substrate. Further,the plurality of gas discharge ports are respectively disposed at theplurality of positions differing in distance from the rotational axisand the processing liquid on the substrate can thus be heated at theplurality of positions that are separated in a radial direction. Thetemperature uniformity of the processing liquid can thereby beincreased.

In the present preferred embodiment, at least one of the followingfeatures may be added to the substrate processing apparatus.

The plurality of discharge ports discharge the processing liquids towarda plurality of liquid landing positions within the upper surface of thesubstrate held by the substrate holding unit and the plurality of gasdischarge ports discharge the gas toward the plurality of blowing-onpositions within the upper surface of the substrate held by thesubstrate holding unit, and the plurality of liquid landing positionsand the plurality of blowing-on positions are shifted such that inregard to the radial direction orthogonal to the rotational axis, ablowing-on position is positioned between two adjacent liquid landingpositions. The number of discharge ports positioned between two adjacentgas discharge ports may be not less than two (see FIG. 17) or may beone.

With this arrangement, the plurality of liquid landing positions and theplurality of blowing-on positions are not aligned in a circumferentialdirection (a direction around the rotational axis) but are shifted inthe radial direction. The etching amount of the substrate decreases withdistance away from a liquid landing position and is the smallest at anintermediate position between two liquid landing positions in the radialdirection. Each blowing-on position is a position between two liquidlanding positions in the radial direction. Temperature decrease of theprocessing liquid at a position between two liquid landing positions isthus suppressed or prevented and improvement is achieved in regard tothe decrease of the etching amount at this position. The processinguniformity is thereby increased.

The processing liquid supplying system further includes a plurality ofdownstream flow passages, each of the plurality of auxiliary upstreamflow passages is a branching upstream flow passage that branches into aplurality of the downstream flow passages, and each auxiliary dischargeport is respectively provided according to each downstream flow passage.

With this arrangement, the flow passages supplying the processingliquids to the plurality of discharge ports are branched into multiplestages. That is, the supply flow passage branches into the plurality ofupstream flow passages (first branching) and the branching upstream flowpassages, included among the plurality of upstream flow passages, branchinto the plurality of downstream flow passages (second branching). Thenumber of discharge ports can thus be increased in comparison to a casewhere the branching upstream flow passages are not included among theplurality of upstream flow passages. The temperature uniformity of theprocessing liquid on the substrate can thereby be increased further andthe processing uniformity can be increased further.

The substrate processing apparatus further includes a chamber housingthe substrate held by the substrate holding unit and the branchingupstream flow passages branch into the plurality of downstream flowpassages inside the chamber.

With this arrangement, upstream ends of the plurality of downstream flowpassages are disposed inside the chamber. The branching upstream flowpassages branch into the plurality of downstream flow passages insidethe chamber. Each downstream flow passage can thus be reduced in length(length in a direction in which the liquid flows) in comparison to acase where the branching upstream flow passages are branched outside thechamber. Temperature decrease of the processing liquid due to heattransfer from the processing liquid to each downstream flow passage canthereby be suppressed.

The processing liquid supplying system further includes an upstreamheater and a plurality of downstream heaters, the upstream heater heatsthe processing liquid, supplied to the supply flow passage, at anupstream temperature, and the plurality of downstream heaters arerespectively connected to the plurality of auxiliary upstream flowpassages at positions further upstream than the plurality of auxiliarydischarge ports and heat the processing liquids flowing through theplurality of auxiliary upstream flow passages, at downstreamtemperatures higher than the upstream temperature.

With this arrangement, the processing liquids that have been heated atthe downstream temperatures higher than the upstream temperature by thedownstream heaters are supplied to the plurality of auxiliary dischargeports from the plurality of auxiliary upstream flow passages and aredischarged from the discharge ports. That is, whereas the processingliquid of the upstream temperature is discharged from the main dischargeport, the processing liquid of higher temperature than the upstreamtemperature is discharged from each auxiliary discharge port. Thetemperatures of the processing liquids supplied to the upper surface ofthe substrate thus increase stepwise with distance away from therotational axis and the temperature uniformity of the processing liquidon the substrate can thus be increased in comparison to a case where theprocessing liquid of the same temperature is discharged from eachdischarge port. The processing uniformity can thus be increased whilereducing the consumption amount of the processing liquid.

The processing liquid supplying system further includes a plurality ofreturn flow passages, a plurality of downstream heaters, and adownstream switching unit, the plurality of return flow passages arerespectively connected to the plurality of auxiliary upstream flowpassages at positions further upstream than the plurality of auxiliarydischarge ports, the plurality of downstream heaters are respectivelyconnected to the plurality of auxiliary upstream flow passages atpositions further upstream than the connection positions of the returnflow passages and the auxiliary upstream flow passages and heat theprocessing liquids flowing through the plurality of auxiliary upstreamflow passages, and the downstream switching unit switches to any of aplurality of states including a discharging state, in which theprocessing liquid supplied to the plurality of upstream flow passagesfrom the supply flow passage is supplied to the plurality of dischargeports, and a discharge stoppage state, in which the processing liquidsupplied to the plurality of upstream flow passages from the supply flowpassage is supplied to the plurality of return flow passages.

With this arrangement, during discharge stoppage, the processing liquidis supplied to the upstream flow passage and heated by the downstreamheaters. The processing liquids heated by the downstream heaters are notdischarged from the plurality of discharge ports but flow from theupstream flow passages into the return flow passages. A state where thetemperatures of the downstream heaters are stable can thus be maintainedeven during discharge stoppage. The discharge of the processing liquidcan thus be restarted immediately.

The processing liquid supplying system further includes a first nozzleand a second nozzle, the plurality of discharge ports include a firstdischarge port, disposed in the first nozzle, and a second dischargeport, disposed in the second nozzle, and are aligned in a plan view inthe radial direction orthogonal to the rotational axis, the first nozzleincludes a first arm portion extending in a horizontal longitudinaldirection and a first tip portion extending downward from a tip of thefirst arm portion, the second nozzle includes a second arm portionextending in the longitudinal direction and a second tip portionextending downward from a tip of the second arm portion, the first armportion and the second arm portion are aligned in a horizontal alignmentdirection orthogonal to the longitudinal direction, and the tip of thefirst arm portion and the tip of the second arm portion are separated inthe longitudinal direction in a plan view such that the tip of the firstarm portion is positioned at the rotational axis side.

With this arrangement, the first discharge port and the second dischargeport are aligned in a plan view in the radial direction. When aplurality of nozzles of the same length are aligned in the horizontaldirection orthogonal to the longitudinal direction so that the pluralityof discharge ports are aligned in a plan view in the radial direction,the entirety of the plurality of nozzles increases in width (see FIG.9). When a plurality of nozzles of different lengths are aligned in avertical direction so that the plurality of discharge ports are alignedin a plan view in the radial direction, the entirety of the plurality ofnozzles increases in height (see FIG. 10A and FIG. 10B).

On the other hand, when the first arm portion and the second arm portionare aligned in the horizontal alignment direction orthogonal to thelongitudinal direction and the tip of the first arm portion and the tipof the second arm portion are shifted in the longitudinal direction in aplan view such that the tip of the first arm portion is positioned atthe rotational axis side, the plurality of discharge ports can bealigned in the radial direction in a plan view while suppressing boththe width and the height of the entirety of the plurality of nozzles(see FIG. 4). The plurality of nozzles and associated members, such as astandby pot, etc., can thereby be made compact.

Another preferred embodiment of the present invention provides asubstrate processing apparatus including a substrate holding unitrotating a substrate around a vertical rotational axis passing through acentral portion of the substrate while holding the substratehorizontally, and a processing liquid supplying system supplying aprocessing liquid to the substrate held by the substrate holding unit.

The processing liquid supplying system includes a supply flow passage, aplurality of upstream flow passages, a plurality of discharge ports, afirst nozzle, and a second nozzle. The supply flow passage guides theprocessing liquid toward the plurality of upstream flow passages. Theplurality of upstream flow passages branch from the supply flow passage,are respectively connected to the plurality of discharge ports, andguide the processing liquids, supplied from the supply flow passage,toward the plurality of discharge ports. The plurality of dischargeports include a first discharge port, disposed in the first nozzle, anda second discharge port, disposed in the second nozzle, are aligned in aplan view in a radial direction orthogonal to the rotational axis, andrespectively discharge the processing liquids, supplied via theplurality of upstream flow passages, toward a plurality of positionswithin an upper surface of the substrate, including an upper surfacecentral portion of the substrate. The first nozzle includes a first armportion extending in a horizontal longitudinal direction and a first tipportion extending downward from a tip of the first arm portion. Thesecond nozzle includes a second arm portion extending in thelongitudinal direction and a second tip portion extending downward froma tip of the second arm portion. The first arm portion and the secondarm portion are aligned in a horizontal alignment direction orthogonalto the longitudinal direction. The tip of the first arm portion and thetip of the second arm portion are separated in the longitudinaldirection in a plan view such that the tip of the first arm portionbeing positioned at the rotational axis side.

With this arrangement, the supply flow passage guiding the processingliquid branches into the plurality of upstream flow passages. The numberof discharge ports can thereby be increased. The processing liquidflowing through the supply flow passage is supplied to the dischargeports from the upstream flow passages and discharged toward the uppersurface of the substrate that rotates around the rotational axis. Theplurality of discharge ports are respectively disposed at the pluralityof positions differing in distance from the rotational axis. Thetemperature uniformity of the processing liquid on the substrate canthus be increased in comparison to a case where the processing liquid isdischarged from just a single discharge port. The processing uniformitycan thereby be increased while reducing the consumption amount of theprocessing liquid.

Further with the present arrangement, the plurality of discharge portsare aligned in a plan view in the radial direction. When a plurality ofnozzles of the same length are aligned in the horizontal directionorthogonal to the longitudinal direction so that the plurality ofdischarge ports are aligned in a plan view in the radial direction, theentirety of the plurality of nozzles increases in width (see FIG. 9).When a plurality of nozzles of different lengths are aligned in avertical direction so that the plurality of discharge ports are alignedin a plan view in the radial direction, the entirety of the plurality ofnozzles increases in height (see FIG. 10A and FIG. 10B).

On the other hand, when the first arm portion and the second arm portionare aligned in the horizontal alignment direction orthogonal to thelongitudinal direction and the tip of the first arm portion and the tipof the second arm portion are shifted in the longitudinal direction in aplan view such that the tip of the first arm portion is positioned atthe rotational axis side, the plurality of discharge ports can bealigned in the radial direction in a plan view while suppressing boththe width and the height of the entirety of the plurality of nozzles(see FIG. 4). The plurality of nozzles and associated members, such as astandby pot, etc., can thereby be made compact.

Another preferred embodiment of the present invention provides asubstrate processing apparatus including a substrate holding unitrotating a substrate around a vertical rotational axis passing through acentral portion of the substrate while holding the substratehorizontally, and a processing liquid supplying system supplying aprocessing liquid to the substrate held by the substrate holding unit.

The processing liquid supplying system includes a supply flow passage, aplurality of upstream flow passages, a plurality of downstream heaters,a collective flow passage, and a slit discharge port. The supply flowpassage branches into the plurality of upstream flow passages and guidesthe processing liquid toward the plurality of upstream flow passages.The plurality of upstream flow passages include a plurality of auxiliaryupstream flow passages having a plurality of auxiliary downstream endsthat are aligned in a radial direction orthogonal to the rotational axisin a plan view and a main upstream flow passage having a main downstreamend disposed further to the rotational axis side than the plurality ofauxiliary downstream ends. The plurality of downstream heaters arerespectively connected to the plurality of auxiliary upstream flowpassages and heat the processing liquids flowing through the pluralityof auxiliary upstream flow passages such that temperatures of theprocessing liquids supplied to the plurality of auxiliary downstreamends increase with increase of distance from the rotational axis to eachauxiliary downstream end. The collective flow passage is connected tothe plurality of auxiliary upstream flow passages. The slit dischargeport is connected to the collective flow passage at a position furtherdownstream than the plurality of auxiliary upstream flow passages, has aslit shape extending in the radial direction between an upper surfacecentral portion of the substrate and an upper surface peripheral edgeportion of the substrate in a plan view, and discharges the processingliquids, supplied from the collective flow passage, toward an uppersurface of the substrate. As long as it is connected to two or more ofthe auxiliary upstream flow passages, the collective flow passage doesnot have to be connected to all of the auxiliary upstream flow passages.

With this arrangement, the processing liquid is supplied from the supplyflow passage to the plurality of upstream flow passages. The processingliquid supplied to the plurality of auxiliary upstream flow passages,included among the plurality of upstream flow passages, is heated by theplurality of downstream heaters. The processing liquids heated by theplurality of downstream heaters are supplied from the plurality ofauxiliary upstream flow passages to the collective flow passage anddischarged from the slit discharge port toward the upper surface of thesubstrate. A band-shaped liquid film extending in the radial directionbetween the upper surface central portion of the substrate and the uppersurface peripheral edge portion of the substrate is thereby formedbetween the slit discharge port and the substrate and lands on arectilinear region within the upper surface of the substrate.

When processing liquids are discharged toward the upper surface of thesubstrate from a plurality of discharge ports that are aligned in theradial direction, the processing liquids land on a plurality of liquidlanding positions (positions at which the processing liquids firstcontact the substrate) that are separated in the radial direction. Ifthe processing liquid is an etching liquid, an etching rate (etchingamount of the substrate per unit time) at a liquid landing position willbe higher than an etching rate at a position between two adjacent liquidlanding positions. The processing uniformity is thus decreased. Suchdecrease of uniformity can thus be prevented by making the processingliquids, discharged from the slit discharge port, land on therectilinear region that is continuous in the radial direction.

Also, the temperatures of the processing liquids supplied to theplurality of auxiliary downstream ends of the plurality of auxiliaryupstream flow passages increase with the increase of distance from therotational axis to the auxiliary downstream ends. The processing liquidsof the same or substantially the same temperatures as the processingliquids supplied to the plurality of auxiliary downstream ends land onpositions directly below the plurality of auxiliary downstream ends. Onthe other hand, a mixed liquid of processing liquids, supplied to two ofthe plurality of auxiliary downstream ends that are adjacent to eachother, lands at each position between the directly-below positions. Thatis, processing liquids that mutually differ in temperature are suppliedto two of the plurality of auxiliary downstream ends that are adjacentto each other, and a processing liquid of a temperature between the twotemperatures lands on a position between the directly-below positions.

The temperature of the processing liquid at each position of the slitdischarge port thus increases stepwise or continuously with distancefrom the rotational axis and the temperature uniformity of theprocessing liquid on the substrate can thus be increased in comparisonto a case where a processing liquid, of uniform temperature isdischarged from the slit discharge port. The processing uniformity canthereby be increased further. Therefore in comparison to a case where aprocessing liquid is made to land on just the upper surface centralportion of the substrate, the processing uniformity can be increasedwhile reducing the consumption amount of the processing liquid suppliedto the substrate.

Also, in substrate processing, it is important, in terms of improvementof processing uniformity, that the processing liquid of the same qualityis supplied to each portion of the substrate. If a tank and a filter,etc., are provided for each upstream flow passage, the processing liquidsupplied to a certain upstream flow passage may differ in quality fromthe processing liquid supplied to another upstream flow passage. On theother hand, with the present preferred embodiment, the processing liquidin the same flow passage (supply flow passage) is supplied to therespective upstream flow passages. The processing liquids of the samequality can thereby be supplied to each portion of the substrate.Further, in comparison to an arrangement where a tank and a filter,etc., are provided according to each upstream flow passage, the numberof parts can be reduced and maintenance work can be simplified.

In the present preferred embodiment, at least one of the followingfeatures may be added to the substrate processing apparatus.

The slit discharge port extends in a radial direction, in a plan view,from the upper surface central portion of the substrate to the uppersurface peripheral edge portion of the substrate.

With this arrangement, the slit discharge port overlaps, in a plan view,with the upper surface central portion and the upper surface peripheraledge portion of the substrate. The processing liquids discharged fromthe slit discharge port land at the same time on the rectilinear regionthat includes the upper surface central portion and the upper surfaceperipheral edge portion of the substrate. The slit discharge portdischarges the processing liquids toward the upper surface of therotating substrate. A relative positional relationship of the substrateand the rectilinear region changes due to the rotation of the substrate.The processing liquids are thereby made to land on the entire uppersurface of the substrate and the processing uniformity can thus beincreased.

In a plan view, a width of the slit discharge port is less than a widthof the auxiliary downstream ends of the auxiliary upstream flowpassages, that is, for example, is less than a maximum value of thewidths of the auxiliary downstream ends. The “width” means a length in ahorizontal direction orthogonal to the radial direction (longitudinaldirection of the slit discharge port).

With this arrangement, the width of the slit discharge port is narrowand therefore a portion of the processing liquid supplied to anauxiliary upstream flow passage spreads in the longitudinal directionwithin the collective flow passage before arriving at the slit dischargeport while the remaining portion of the processing liquid supplied tothe auxiliary upstream flow passage arrives at the slit discharge portwithout spreading in the longitudinal direction of the slit dischargeport within the collective flow passage. A portion of the processingliquid is thus mixed with the processing liquid supplied to anotherauxiliary upstream flow passage in an interior of the collective passageor in a space between the substrate and the slit discharge port. Thetemperatures of the processing liquids supplied to the substrate canthereby be increased stepwise or continuously with distance away fromthe rotational axis.

A width of a downstream end of the collective flow passage is equal tothe width of the slit discharge port. Preferably, a width of an upstreamend of the collective flow passage is not less than a width of theauxiliary downstream ends. The width of the collective flow passage maydecrease continuously or decrease stepwise from the upstream end to thedownstream end. If the width of the upstream end of the collective flowpassage is not less than the width of auxiliary downstream ends, theflow of the processing liquid within the collective flow passage isunlikely to be obstructed at the upstream end of the collective flowpassage. Pressure decrease of the processing liquid discharged from theslit discharge port can thus be reduced in comparison to a case wherethe width of the upstream end of the collective flow passage is lessthan the width of auxiliary downstream ends.

The processing liquid supplying system further includes a plurality ofreturn flow passages and a downstream switching unit, the plurality ofreturn flow passages are respectively connected to the plurality ofauxiliary upstream flow passages at positions further downstream thanthe plurality of downstream heaters, and the downstream switching unitswitches to any of a plurality of states including a discharging state,in which the processing liquid supplied to the plurality of upstreamflow passages from the supply flow passage is supplied to the slitdischarge port, and a discharge stoppage state, in which the processingliquid supplied to the plurality of upstream flow passages from thesupply flow passage is supplied to the plurality of return flowpassages.

With this arrangement, during discharge stoppage, the processing liquidis supplied to the upstream flow passage and heated by the downstreamheaters. The processing liquids heated by the downstream heaters are notdischarged from the slit discharge port but flow from the upstream flowpassages into the return flow passages. A state where the temperaturesof the downstream heaters are stable can thus be maintained even duringdischarge stoppage. The discharge of the processing liquid can thus berestarted immediately.

The above and other elements, features, steps, characteristics andadvantages of the present invention will become more apparent from thefollowing detailed description of the preferred embodiments withreference to the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of a processing liquid supplying system of asubstrate processing apparatus according to a first preferred embodimentof the present invention and shows the processing liquid supplyingsystem in a discharging state.

FIG. 2 is a schematic view of a processing liquid supplying system ofthe substrate processing apparatus according to the first preferredembodiment of the present invention and shows the processing liquidsupplying system in a discharge stoppage state.

FIG. 3 is a schematic front view of an interior of a processing unitincluded in the substrate processing apparatus.

FIG. 4 is a schematic plan view of the interior of the processing unitincluded in the substrate processing apparatus.

FIG. 5 is a schematic front view of a plurality of nozzles.

FIG. 6 is a schematic plan view of the plurality of nozzles.

FIG. 7 is a process flowchart for describing an example of substrateprocessing executed by the substrate processing apparatus.

FIG. 8 is a graph of etching amount distributions of substrates.

FIG. 9 is a schematic plan view of a plurality of nozzles according to afirst modification example of the first preferred embodiment.

FIG. 10A and FIG. 10B are schematic views of a plurality of nozzlesaccording to a second modification example of the first preferredembodiment, with FIG. 10A being a schematic front view of the pluralityof nozzles and FIG. 10B being a schematic plan view of the plurality ofnozzles.

FIG. 11 is a schematic front view of a plurality of nozzles according toa third modification example of the first preferred embodiment.

FIG. 12 is a time chart of chemical liquid discharge timings accordingto a fourth modification example of the first preferred embodiment.

FIG. 13 is a schematic front view of a discharge position adjusting unitaccording to a fifth modification example of the first preferredembodiment.

FIG. 14 is a graph showing a conceptual image of a thickness of a thinfilm before and after processing and a temperature of a processingliquid supplied to a substrate.

FIG. 15 is a schematic plan view of a plurality of nozzles according toa second preferred embodiment of the present invention.

FIG. 16 is a graph of etching amount distributions of substrates.

FIG. 17 is a schematic front view of a plurality of nozzles and aplurality of gas nozzles according to a third preferred embodiment ofthe present invention.

FIG. 18 is a schematic plan view of the plurality of nozzles and theplurality of gas nozzles.

FIG. 19 is a process flowchart for describing an example of substrateprocessing executed by the substrate processing apparatus.

FIG. 20 is a graph of etching amount distributions of substrates.

FIG. 21 is a schematic view of a processing liquid supplying system of asubstrate processing apparatus according to a fourth preferredembodiment of the present invention and shows the processing liquidsupplying system in a discharging state.

FIG. 22 is a schematic view of a processing liquid supplying system ofthe substrate processing apparatus according to the fourth preferredembodiment of the present invention and shows the processing liquidsupplying system in a discharge stoppage state.

FIG. 23 is a schematic front view of an interior of a processing unitincluded in the substrate processing apparatus.

FIG. 24 is a schematic plan view of the interior of the processing unitincluded in the substrate processing apparatus.

FIG. 25 is a schematic partial sectional view of a plurality of nozzlesand a nozzle head as viewed horizontally.

FIG. 26 is a schematic plan view of the plurality of nozzles and thenozzle head.

FIG. 27 is a schematic perspective view of the plurality of nozzles andthe nozzle head.

FIG. 28 is a graph of etching amount distributions of substrates.

FIG. 29A and FIG. 29B are schematic views of a plurality of nozzlesaccording to a second modification example of the fourth preferredembodiment, with FIG. 29A being a schematic front view of the pluralityof nozzles and FIG. 29B being a schematic plan view of the plurality ofnozzles.

FIG. 30 is a schematic partial sectional view of a plurality of nozzlesand a nozzle head according to another preferred embodiment of thepresent invention as viewed horizontally.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

FIG. 1 and FIG. 2 are schematic views of a processing liquid supplyingsystem of a substrate processing apparatus 1 according to a preferredembodiment of the present invention. FIG. 1 shows the processing liquidsupplying system in a discharging state and FIG. 2 shows the processingliquid supplying system in a discharge stoppage state.

The substrate processing apparatus 1 is a single substrate processingtype apparatus that processes a disk-shaped substrate W, such as asemiconductor wafer, etc., one by one. The substrate processingapparatus 1 includes a processing unit 2 that processes the substrate Wwith a processing liquid, a transfer robot (not shown) that conveys thesubstrate W to the processing unit 2, and a controller 3 that controlsthe substrate processing apparatus 1. The controller 3 is a computerthat includes a computing portion and a storage portion.

The substrate processing apparatus 1 includes a plurality of fluid boxes5, each housing fluid devices including a valve 51 that controlssupplying of the processing liquid to the processing unit 2 and itsstoppage, and a plurality of storage boxes 6, each housing a tank 41storing the processing liquid to be supplied to the processing unit 2via the fluid boxes 5. The processing unit 2 and the fluid boxes 5 aredisposed inside a frame 4 of the substrate processing apparatus 1. Achamber 7 of the processing unit 2 and the fluid boxes 5 are aligned ina horizontal direction. The storage boxes 6 are disposed outside theframe 4. The storages boxes 6 may be disposed inside the frame 4.

FIG. 3 is a schematic front view of an interior of the processing unit2. FIG. 4 is a schematic plan view of the interior of the processingunit 2.

As shown in FIG. 3, the processing unit 2 includes a box-shaped chamber7, a spin chuck 11 rotating the substrate W around a vertical rotationalaxis A1 passing through a central portion of the substrate W whileholding the substrate W horizontally inside the chamber 7, and acylindrical cup 15 receiving the processing liquid expelled from thesubstrate W.

As shown in FIG. 4, the chamber 7 includes a box-shaped partition wall8, provided with a carry-in/carry-out port 8 a through which thesubstrate W passes, and a shutter 9 that opens and closes thecarry-in/carry-out port 8 a. The shutter 9 is movable with respect tothe partition wall 8 between an open position at which thecarry-in/carry-out port 8 a is open and a closed position (positionshown in FIG. 4) at which the carry-in/carry-out port 8 a is closed. Theunillustrated transfer robot carries the substrate W into the chamber 7through the carry-in/carry-out port 8 a and carries out the substrate Wfrom the chamber 7 through the carry-in/carry-out port 8 a.

As shown in FIG. 3, the spin chuck 11 includes a disk-shaped spin base12 that is held in a horizontal orientation, a plurality of chuck pins13 that hold the substrate W in a horizontal orientation above the spinbase 12, and a spin motor 14 that rotates the plurality of chuck pins 13to rotate the substrate W around a rotational axis A1. The spin chuck 11is not restricted to a clamping type chuck in which the plurality ofchuck pins 13 are brought into contact with a peripheral end surface ofthe substrate W, and may be a vacuum type chuck in which a rear surface(lower surface) of the substrate W that is a non-device forming surfaceis suctioned onto an upper surface of the spin base 12 to hold thesubstrate horizontally.

As shown in FIG. 3, the cup 15 includes a cylindrical splash guard 17that surrounds the spin chuck 11 around the rotational axis A1 and acircular cylindrical outer wall 16 surrounding the splash guard 17around the rotational axis A1. The processing unit 2 includes a guardraising/lowering unit 18 that raises and lowers the splash guard 17vertically between an upper position (position shown in FIG. 3) at whichan upper end of the splash guard 17 is positioned higher than a positionat which the spin chuck 11 holds the substrate W and a lower position atwhich the upper end of the splash guard 17 is positioned lower than theposition at which the spin chuck 11 holds the substrate W.

As shown in FIG. 3, the processing unit 2 includes a rinse liquid nozzle21 that discharges a rinse liquid downward toward an upper surface ofthe substrate W held by the spin chuck 11. The rinse liquid nozzle 21 isconnected to a rinse liquid piping 22 in which a rinse liquid valve 23is interposed. The processing unit 2 may include a nozzle moving unitthat moves the rinse liquid nozzle 21 between a processing position anda standby position.

When the rinse liquid valve 23 is opened, the rinse liquid is suppliedfrom the rinse liquid piping 22 to the rinse liquid nozzle 21 anddischarged from the rinse liquid nozzle 21. The rinse liquid is, forexample, pure water (deionized water). The rinse liquid is notrestricted to pure water and may instead be any of carbonated water,electrolyzed ion water, hydrogen water, ozone water, or aqueoushydrochloric acid solution of dilute concentration (of, for example,approximately 10 to 100 ppm), etc.

As shown in FIG. 4, the processing unit 2 includes a plurality ofnozzles 26 (first nozzle 26A, second nozzle 26B, third nozzle 26C, andfourth nozzle 26D) that discharge chemical liquids downward, a holder 25that holds each of the plurality of nozzles 26, and a nozzle moving unit24 that moves the holder 25 to move the plurality of nozzles 26 betweena processing position (position indicated by alternate long and twoshort dashes lines in FIG. 4) and a standby position (position indicatedby solid lines in FIG. 4).

Representative examples of the chemical liquid include etching liquids,such as TMAH (tetramethylammonium hydroxide aqueous solution), etc., andresist removing liquids, such as SPM (sulfuric acid/hydrogen peroxidemixture), etc. The chemical liquid is not restricted to TMAH and SPM,and may be a liquid containing at least one of sulfuric acid, aceticacid, nitric acid, hydrochloric acid, hydrofluoric acid, ammonia water,hydrogen peroxide water, an organic acid (for example, citric acid,oxalic acid, etc.), an organic alkali besides TMAH, a surfactant, and acorrosion inhibitor.

As shown in FIG. 3, each of the nozzles 26 includes a main nozzle body27 that is cantilevered by the holder 25. The main nozzle body 27includes an arm portion 28 extending in a horizontal longitudinaldirection D1 from the holder 25 and a tip portion 29 extending downwardfrom a tip 28 a of the arm portion 28. The tip 28 a of the arm portion28 means a portion disposed furthest in the longitudinal direction D1from the holder 25 in a plan view.

As shown in FIG. 4, the plurality of arm portions are aligned in ahorizontal alignment direction D2, orthogonal to the longitudinaldirection D1, in the order of the first nozzle 26A to the fourth nozzle26D. The plurality of arm portions 28 are disposed at the same height.An interval between two arm portions 28 that are adjacent in thealignment direction D2 may be the same as any of the other intervals ormay differ from at least one of the other intervals. FIG. 4 shows anexample where the plurality of arm portions 28 are disposed at equalintervals.

Lengths of the plurality of arm portions 28 in the longitudinaldirection D1 decrease in the order of the first nozzle 26A to the fourthnozzle 26D. Tips of the plurality of nozzles 26 (the tips 28 a of theplurality of arm portions 28) are shifted in the longitudinal directionD1 so as to be aligned in the order of the first nozzle 26A to thefourth nozzle 26D in regard to the longitudinal direction D1. The tipsof the plurality of nozzles 26 are aligned rectilinearly in a plan view.

The nozzle moving unit 24 makes the holder 25 pivot around a nozzlepivoting axis A2 extending vertically at a periphery of the cup 15 tomove the plurality of nozzles 26 along an arcuate path passing thesubstrate W in a plan view. The plurality of nozzles 26 are therebymoved horizontally between the processing position and the standbyposition. The processing unit 2 includes a bottomed cylindrical standbypot 35 that is disposed below the standby position of the plurality ofnozzles 26. The standby pot 35 is disposed at a periphery of the cup 15in a plan view.

The processing position is a position at which the chemical liquidsdischarged from the plurality of nozzles 26 land on the upper surface ofthe substrate W. At the processing position, the plurality of nozzles 26and the substrate W overlap in a plan view and the tips of the pluralityof nozzles 26 are aligned in a radial direction Dr in the order of thefirst nozzle 26A to the fourth nozzle 26D from the rotational axis A1side. In this state, the tip of the first nozzle 26A overlaps with acentral portion of the substrate W in a plan view and the tip of thefourth nozzle 26D overlaps with a peripheral edge portion of thesubstrate W in a plan view.

The standby position is a position to which the plurality of nozzles 26are retracted so that the plurality of nozzles 26 and the substrate W donot overlap in a plan view. At the standby position, the tips of theplurality of nozzles 26, in a plan view, are positioned outside the cup15 and along an outer circumferential surface of the cup 15 (outercircumferential surface of the outer wall 16) and are aligned in acircumferential direction (direction around the rotational axis A1) inthe order of the first nozzle 26A to the fourth nozzle 26D. Theplurality of nozzles 26 are disposed so as to move away from therotational axis A1 in the order of the first nozzle 26A to the fourthnozzle 26D.

The plurality of nozzles 26 shall now be described with reference toFIG. 5 and FIG. 6. Thereafter, the processing liquid supplying systemshall be described.

In the following description, “first” and “A” may be added to thebeginning and the end of an arrangement corresponding to the firstnozzle 26A. For example, an upstream flow passage 48 associated with thefirst nozzle 26A may be referred to as the “first upstream flow passage48A.” The same applies to arrangements associated with the second nozzle26B to the fourth nozzle 26D.

Also in the following description, a temperature at which the processingliquid is heated by an upstream heater 43 may be referred to as the“upstream temperature” and a temperature at which the processing liquidis heated by a downstream heater 53 may be referred to as the“downstream temperature.” Temperatures at which the processing liquidsare heated by a second downstream heater 53 to a fourth downstreamheater 53 may be referred to respectively as the “second downstreamtemperature” to the “fourth heating temperature.”

As shown in FIG. 5, each main nozzle body 27 includes a resin tube 30that guides the processing liquid, a core bar 31 including cylindricalcross section that surrounds the resin tube 30, and a resin coating 32including cylindrical cross section that surrounds an outer surface ofthe core bar 31. Each of the nozzles 26 besides the first nozzle 26Afurther includes a nozzle head 33 mounted on the tip portion 29 of themain nozzle body 27.

Each main nozzle body 27 defines a single flow passage extending alongthe main nozzle body 27. Each nozzle head 33 defines a plurality of flowpassages guiding the processing liquid supplied from the main nozzlebody 27. The flow passage of the main nozzle body 27 defines a dischargeport 34 opening at an outer surface of the main nozzle body 27. Theplurality of flow passages of the nozzle head 33 define a plurality ofdischarge ports 34 opening at an outer surface of the nozzle head 33.The flow passage of the main nozzle body 27 corresponds to a portion ofan upstream flow passage 48 to be described below. Each of the flowpassages of the nozzle head 33 corresponds to a downstream flow passage52 to be described below. Downstream ends of the first upstream flowpassage 48A to the fourth upstream flow passage 48D are respectivelydisposed at a plurality of positions differing in distance from therotational axis A1.

FIG. 5 and FIG. 6 show an example where the total number of dischargeports 34 disposed in the plurality of nozzles 26 is ten. The firstnozzle 26A includes a single discharge port 34 disposed in the mainnozzle body 27. Each of the nozzles 26 besides the first nozzle 26Aincludes three discharge ports 34 disposed in the nozzle head 33. Thethree discharge ports 34 disposed in the same nozzle head 33 areconstituted of an inner discharge port that is closest to the rotationalaxis A1 among the three discharge ports 34, an outer discharge port thatis furthest from the rotational axis A1 among the three discharge ports34, and a middle discharge port disposed between the inner dischargeport and the outer discharge port.

As shown in FIG. 6, the plurality of discharge ports 34 are alignedrectilinearly in a plan view. An interval between the two dischargeports 34 at the respective ends is not more than a radius of thesubstrate W. An interval between two discharge ports 34 that areadjacent may be the same as any of the other intervals or may differfrom at least one of the other intervals. Also, the plurality ofdischarge ports 34 may be disposed at the same height or maybe disposedat two or more different heights.

When the plurality of nozzles 26 are disposed at the processingposition, the plurality of discharge ports 34 are respectively disposedat a plurality of positions that differ in distance (shortest distancein a plan view) from the rotational axis A1. In this state, an innermostdischarge port (first discharge port 34A) that is closest to therotational axis A1 among the plurality of discharge ports 34 is disposedabove a central portion of the substrate W, and an outermost dischargeport (fourth discharge port 34D) that is furthest from the rotationalaxis A1 among the plurality of discharge ports 34 is disposed above aperipheral edge portion of the substrate W, The plurality of dischargeports 34 are aligned in the radial direction Dr in a plan view.

The first discharge port 34A disposed in the first nozzle 26A is a maindischarge port that discharges the processing liquid toward an uppersurface central portion of the substrate W. The second discharge port34B to the fourth discharge port 34D that are disposed in the respectivenozzles 26 besides the first nozzle 26A are a plurality of auxiliarydischarge ports that discharge the processing liquids toward a portionof the upper surface of the substrate W besides the central portion. Thefirst upstream flow passage 48A connected to the first discharge port34A is a main upstream flow passage and the second upstream flow passage48B to the fourth upstream flow passage 48D that are connected to thesecond discharge port 34B to the fourth discharge port 34D are aplurality of auxiliary upstream flow passages.

As shown in FIG. 5, each discharge port 34 discharges the chemicalliquid in a discharge direction perpendicular to the upper surface ofthe substrate W. The plurality of discharge ports 34 discharge thechemical liquids toward a plurality of liquid landing positions withinthe upper surface of the substrate W. The plurality of liquid landingpositions are separate positions that differ in distance from therotational axis A1. If the liquid landing position that is closest tothe rotational axis A1 among the plurality of liquid landing positionsis referred to as the “first liquid landing position” and the liquidlanding position that is second closest to the rotational axis A1 amongthe plurality of liquid landing positions is referred to as the “secondliquid landing position,” the chemical liquid discharged from the firstdischarge port 34A lands on the first liquid landing position and thechemical liquid discharged from the second discharge port 34B lands onthe second liquid landing position.

The processing liquid supplying system shall now be described in detailwith reference to FIG. 1 and FIG. 2.

The processing liquid supplying system includes a chemical liquid tank41 storing the chemical liquid, a chemical liquid flow passage 42guiding the chemical liquid fed from chemical liquid tank 41, anupstream heater 43 heating the chemical liquid flowing inside thechemical liquid flow passage 42 at the upstream temperature higher thanroom temperature (for example, of 20 to 30° C.) to adjust thetemperature of the chemical liquid inside the chemical liquid tank 41, apump 44 feeding the chemical liquid inside the chemical liquid tank 41to the chemical liquid flow passage 42, and a circulation flow passage40 returning the chemical liquid inside the chemical liquid flow passage42 to the chemical liquid tank 41.

The processing liquid supplying system includes a supply valve 45 thatopens and closes the chemical liquid flow passage 42, a circulationvalve 46 that opens and closes the circulation flow passage 40, and asupply flow passage 47 connected to the chemical liquid flow passage 42.An upstream switching unit includes the supply valve 45.

The processing liquid supplying system includes the plurality ofupstream flow passages 48 guiding the liquid supplied from the supplyflow passage 47 to the plurality of discharge ports 34, a plurality offlowmeters 49 detecting flow rates of the liquids flowing inside theplurality of upstream flow passages 48, a plurality of flow controlvalves 50 that change the flow rates of the liquids flowing inside theplurality of upstream flow passages 48, and a plurality of dischargevalves 51 respectively opening and closing the plurality of upstreamflow passages 48. Although unillustrated, each flow control valve 50includes a main valve body that opens and closes the flow passage and anactuator that changes an open degree of the main valve body. Theactuator may be a pneumatic actuator or an electric actuator or anactuator besides these.

The processing liquid supplying system includes the plurality ofdownstream flow passages 52 that guide the liquids supplied from theupstream flow passages 48 to the plurality of discharge ports 34. Thedownstream end of each of the upstream flow passages 48 besides thefirst upstream flow passage 48A branches into a plurality of downstreamflow passage 52. That is, each of the upstream flow passages 48 besidesthe first upstream flow passage 48A is a branching upstream flow passagethat branches into a plurality of downstream flow passage 52.

FIG. 1 and FIG. 2 show an example where each branching upstream flowpassage branches into two downstream flow passages 52. FIG. 5 shows anexample where each branching upstream flow passage branches into threedownstream flow passages 52. The three downstream flow passages 52branching from the second upstream flow passage 48B are respectivelyconnected to the three discharge ports 34 (the inner discharge port,middle discharge port, and the outer discharge port) disposed in thesame nozzle head 33. The same as the second upstream flow passage 48Bapplies to the third upstream flow passage 48C and the fourth upstreamflow passage 48D. The first upstream flow passage 48A is connected tothe first discharge port 34A disposed in the first nozzle 26A.

The processing liquid supplying system includes a plurality ofdownstream heaters 53 that heat the liquids flowing inside the pluralityof upstream flow passages 48 besides the first upstream flow passage 48Aat downstream temperatures higher than the upstream temperature. Theprocessing liquid supplying system further includes a plurality ofreturn flow passages 54, respectively connected to the plurality ofupstream flow passages 48 besides the first upstream flow passage 48A atpositions further downstream than the plurality of downstream heaters53, and a plurality of return valves 55, respectively opening andclosing the plurality of return flow passages 54. A downstream switchingunit includes the plurality of discharge valves 51 and the plurality ofreturn valves 55.

The processing liquid supplying system includes a cooler 56 cooling thechemical liquids supplied from the plurality of return flow passages 54and a tank recovery flow passage 57 guiding the chemical liquid from thecooler 56 to the chemical liquid tank 41. The chemical liquids suppliedfrom the plurality of return flow passage 54 to the cooler 56 are madecloser in temperature to the upstream temperature by the cooler 56 andthereafter guided via the tank recovery flow passage 57 to the chemicalliquid tank 41. The cooler 56 may be a water cooled unit or an aircooled unit or may be a cooling unit other than these.

The processing liquid supplying system in a discharging state in whichthe chemical liquids are discharged from the plurality of dischargeports 34 shall now be described with reference to FIG. 1. In FIG. 1, anopen valve is indicated in black and a closed valve is indicated inwhite.

The chemical liquid inside the chemical liquid tank 41 is fed to thechemical liquid flow passage 42 by the pump 44. The chemical liquid fedby the pump 44 is heated by the upstream heater 43 and thereafter flowsfrom the chemical liquid flow passage 42 to the supply flow passage 47and flows to the plurality of upstream flow passages 48 from the supplyflow passage 47. The chemical liquids supplied to the plurality ofbranching upstream flow passages, i.e. the plurality of upstream flowpassages 48 besides the first upstream flow passage 48A are heated bythe downstream heaters 53 and thereafter flow to the plurality ofdownstream flow passage 52.

The chemical liquid inside the first upstream flow passage 48A issupplied to the single first discharge port 34A disposed in the firstnozzle 26A. The chemical liquid inside the second upstream flow passage48B is supplied via the plurality of downstream flow passages 52 to theplurality of second discharge ports 34B disposed in the second nozzle26B. The same as the second upstream flow passage 48B applies to thethird upstream flow passage 48C and the fourth upstream flow passage48D. The chemical liquids are thereby discharged from all dischargeports 34.

The heating temperatures (downstream temperatures) of the processingliquids by the downstream heaters 53 are higher than the heatingtemperature (upstream temperature) of the processing liquid by theupstream heater 43. The second to fourth downstream temperaturesincrease in the order of the second to the fourth downstreamtemperatures. The first discharge port 34A discharges the chemicalliquid of the upstream temperature. Each of the second discharge ports34B discharges the chemical liquid of the second downstream temperature.Each of the third discharge ports 34C discharges the chemical liquid ofthe third downstream temperature. Each of the fourth discharge ports 34Ddischarges the chemical liquid of the fourth downstream temperature. Thetemperatures of the chemical liquids discharged from the plurality ofdischarge ports 34 thus increase stepwise with distance away from therotational axis A1.

The processing liquid supplying system in a discharge stoppage state inwhich the discharges of chemical liquids from the plurality of dischargeports 34 are stopped shall now be described with reference to FIG. 2. InFIG. 2, an open valve is indicated in black and a closed valve isindicated in white.

The chemical liquid inside the chemical liquid tank 41 is fed to thechemical liquid flow passage 42 by the pump 44. A portion of thechemical liquid fed by the pump 44 is heated by the upstream heater 43and thereafter returned to the chemical liquid tank 41 via thecirculation flow passage 40. The remaining portion of the chemicalliquid fed by the pump 44 flows from the chemical liquid flow passage 42to the supply flow passage 47 and flows from the supply flow passage 47to the plurality of upstream flow passages 48 besides the first upstreamflow passage 48A.

The chemical liquid inside the second upstream flow passage 48 is heatedby the downstream heater 53 associated with the second upstream flowpassage 48B and thereafter flows via the return flow passage 54 to thecooler 56. The same as the second upstream flow passage 48B applies tothe third upstream flow passage 48C and the fourth upstream flow passage48D. The chemical liquids supplied to the cooler 56 are cooled by thecooler 56 and return to the chemical liquid tank 41 via the tankrecovery flow passage 57. All of the chemical liquid fed to the chemicalliquid flow passage 42 by the pump 44 is thereby returned to thechemical liquid tank 41.

The temperature of the processing liquid may have a large influence onthe processing of the substrate W. If the downstream heaters 53 arestopped during discharge stoppage, it will take time for thetemperatures of the processing liquids, heated by the downstream heaters53, to stabilize at the intended temperatures when operation of thedownstream heaters 53 is restarted. The discharge of processing liquidthus cannot be restarted immediately and throughput decreases.

As described above, even during discharge stoppage, the chemical liquidsflow to the downstream heaters 53 and the downstream heaters 53 heat thechemical liquids. A state where the temperatures of the downstreamheaters 53 are stable can thus be maintained. Further, the chemicalliquids heated by the downstream heaters 53 are returned to the chemicalliquid tank 41 and consumption amount of the chemical liquid can thus bereduced. Moreover, the chemical liquid that is cooled by the cooler 56is returned to the chemical liquid tank 41 and therefore variation oftemperature of the chemical liquid inside the chemical liquid tank 41can be suppressed.

FIG. 7 is a process flowchart for describing an example of processing ofthe substrate W executed by the substrate processing apparatus 1. Therespective operations described below are executed by the controller 3controlling the substrate processing apparatus 1. FIG. 3 and FIG. 4shall be referenced in the following description. FIG. 7 shall bereferenced where suitable.

When the substrate W is to be processed by the processing unit 2, thesubstrate W is carried into the interior of the chamber 7 by a hand (notshown) of the transfer robot in a state where the plurality of nozzles26 are retracted from above the spin chuck 11 and the splash guard 17 ispositioned at the lower position. The substrate W is thereby placed, ina state where the front surface is faced up, on the plurality of chuckpins 13. Thereafter, the hand of the transfer robot is retracted fromthe interior of the chamber 7 and the carry-in/carry-out port 8 a of thechamber 7 is closed by the shutter 9.

After the substrate W has been placed on the plurality of chuck pins 13,the plurality of chuck pins 13 are pressed against peripheral edgeportions of the substrate W and the substrate W is gripped by theplurality of chuck pins 13. Also, the guard raising/lowering unit 18moves the splash guard 17 from the lower position to the upper position.The upper end of the splash guard 17 is thereby disposed higher than thesubstrate W. Thereafter, the spin motor 14 is driven to start rotationof the substrate W. The substrate W is thereby rotated at apredetermined liquid processing speed (of, for example, several hundredrpm).

Thereafter, the nozzle moving unit 24 moves the plurality of nozzles 26from the standby position to the processing position. The plurality ofdischarge ports 34 are thereby overlapped with the substrate W in a planview. Thereafter, the plurality of discharge valves 51, etc., arecontrolled and the chemical liquids are discharged at the same time fromthe plurality of nozzles 26 (step S1 of FIG. 7). The plurality ofnozzles 26 discharge the chemical liquids in a state where the nozzlemoving unit 24 keeps the plurality of nozzles 26 still. When apredetermined time elapses from the opening of the plurality ofdischarge valves 51, the discharges of chemical liquids from theplurality of nozzles 26 are stopped at the same time (step S2 of FIG.7). Thereafter, the nozzle moving unit 24 moves the plurality of nozzles26 from the processing position to the standby position.

The chemical liquids discharged from the plurality of nozzles 26 land onthe upper surface of the rotating substrate W and thereafter flowoutward (in the direction away from the rotational axis A1) along theupper surface of the substrate W due to a centrifugal force. Thechemical liquid that reaches the upper surface peripheral edge portionof the substrate W is scattered to a periphery of the substrate W andreceived by an inner peripheral surface of the splash guard 17. Thechemical liquid is thereby supplied to the entire upper surface of thesubstrate W and a liquid film of the chemical liquid that covers theentire upper surface of the substrate W is formed on the substrate W.The entire upper surface of the substrate W is thereby processed by thechemical liquid.

After the discharges of chemical liquids from the plurality of nozzles26 have been stopped, the rinse liquid valve 23 is opened and dischargeof the rinse liquid (pure water) from the rinse liquid nozzle 21 isstarted (step S3 of FIG. 7). The chemical liquid on the substrate W isthereby rinsed off by the rinse liquid and a liquid film of the rinseliquid that covers the entire upper surface of the substrate W isformed. When a predetermined time elapses from the opening of the rinseliquid valve 23, the rinse liquid valve 23 is closed and the dischargeof the rinse liquid from the rinse liquid nozzle 21 is stopped (step S4of FIG. 7).

After the discharge of the rinse liquid from the rinse liquid nozzle 21has been stopped, the substrate W is accelerated in the rotationaldirection by the spin motor 14 and the substrate W is rotated at adrying speed (of, for example, several thousand rpm) higher than theliquid processing speed (step S5 of FIG. 7). The rinse liquid attachedto the substrate W is thereby spun off to the periphery of the substrateW and the substrate W is dried. When a predetermined time elapses fromthe start of high speed rotation of the substrate W, the rotation of thespin motor 14 and the substrate W is stopped.

After the rotation of the substrate W has been stopped, the guardraising/lowering unit 18 moves the splash guard 17 from the upperposition to the lower position. Further, the holding of the substrate Wby the plurality of chuck pins 13 is released. The transfer robot makesits hand enter the interior of the chamber 7 in the state where theplurality of nozzles 26 are retracted from above the spin chuck 11 andthe splash guard 17 is positioned at the lower position. Thereafter, thetransfer robot uses the hand to take the substrate W on the spin chuck11 and carries out the substrate W from the chamber 7.

FIG. 8 is a graph of etching amount distributions of substrates W.

The processing conditions of the substrates W of measurement A tomeasurement C shown in FIG. 8 are the same with the exception of thenozzles that discharge the chemical liquids.

The measurement A indicates the etching amount distribution when asubstrate W is etched by making a plurality of discharge ports 34 (tendischarge ports 34) discharge the chemical liquids while keeping stillthe plurality of nozzles 26.

The measurement B indicates the etching amount distribution when asubstrate W is etched by making a plurality of discharge ports 34 (fourdischarge ports 34) discharge the chemical liquids while keeping stillthe plurality of nozzles 26 from which all nozzle heads 33 have beenremoved. That is, the measurement B indicates the etching amountdistribution when the four discharge ports 34 (corresponding to thefirst discharge port 34A) respectively disposed in the four main nozzlebodies 27 are made to discharge the chemical liquids.

The measurement C indicates the etching amount distribution when just asingle discharge port 34 is made to discharge the chemical liquid andthe liquid landing position of the chemical liquid is fixed at the uppersurface central portion of the substrate W.

With the measurement C, the etching amount decreases with distance awayfrom the central portion of the substrate W and the etching amountdistribution exhibits a peak-shaped curve. That is, the etching amountis greatest at the liquid landing position of the chemical liquid anddecreases with distance away from the liquid landing position. On theother hand, with the measurement A and the measurement B, the etchingamounts at positions besides the central portion of the substrate W areincreased and etching uniformity is greatly improved in comparison tothe measurement C.

With the measurement B, seven peaks are formed. The apex of the centralpeak is at a position corresponding to the innermost liquid landingposition and the apexes of the two peaks at outer sides thereof are atpositions corresponding to the second liquid landing position from theinner side. The positions of the apexes of the two peaks further to theouter sides are positions corresponding to the third liquid landingposition from the inner side, and the positions of the two outermostpeaks are positions corresponding to the fourth liquid landing positionfrom the inner side.

With the measurement A, a plurality of peaks corresponding to theplurality of liquid landing positions are formed similarly to themeasurement B. Whereas with the measurement B, the number of dischargeports 34 is four, with the measurement A, the number of discharge ports34 is ten and therefore the number of peaks is increased. Further incomparison to the measurement B, the curve indicating the etching amountdistribution is closer to a straight line extending in a right/leftdirection (a straight line of fixed etching amount) and the etchinguniformity is improved.

As described above, with the present preferred embodiment, the supplyflow passage 47 that guides the processing liquid is branched into theplurality of upstream flow passages 48. The number of discharge ports 34can thereby be increased. Further, the branching upstream flow passagesbranching into the plurality of downstream flow passages 52 are includedin the plurality of upstream flow passages 48 and the number ofdischarge ports 34 can thus be increased further.

The processing liquid flowing through the supply flow passage 47 issupplied to the discharge ports 34 from the upstream flow passages 48 orthe downstream flow passages 52 and discharged toward the upper surfaceof the substrate W that rotates around the rotational axis A1. Theplurality of discharge ports 34 are respectively disposed at theplurality of positions differing in distance from the rotational axisA1. Temperature uniformity of the processing liquid on the substrate Wcan thus be increased in comparison to a case where the processingliquid is discharged from just a single discharge port 34. Theprocessing uniformity can thereby be increased while reducing theconsumption amount of the processing liquid.

Also with the present preferred embodiment, the processing liquids thathave been heated at the downstream temperatures higher than the upstreamtemperature by the downstream heaters 53 are supplied to the dischargeports 34, besides the innermost discharge port (the first discharge port34A), from the upstream flow passages 48 besides the innermost upstreamflow passage (the first upstream flow passage 48A) and are dischargedfrom the discharge ports 34. That is, whereas the processing liquid ofthe upstream temperature is discharged from the innermost dischargeport, the processing liquid of higher temperature than the upstreamtemperature is discharged from each of the discharge ports 34 positionedfurther to the outer side than the innermost discharge port.

The temperatures of the processing liquids supplied to the upper surfaceof the substrate W thus increase stepwise with distance away from therotational axis A1 and the temperature uniformity can thus be increasedin comparison to a case where the processing liquid of the sametemperature is discharged from each discharge port 34. The processinguniformity can thereby be increased while reducing the consumptionamount of the processing liquid.

Also with the present preferred embodiment, the upstream ends of theplurality of downstream flow passages 52 are disposed inside the chamber7. The branching upstream flow passages branch into the plurality ofdownstream flow passages 52 inside the chamber 7. Each downstream flowpassage 52 can thus be reduced in length (length in a direction in whichthe liquid flows) in comparison to a case where the branching upstreamflow passages are branched outside the chamber 7. Temperature decreaseof the processing liquid due to heat transfer from the processing liquidto each downstream flow passage 52 can thereby be suppressed.

Also with the present preferred embodiment, the upstream ends of theplurality of upstream flow passages 48 are disposed inside the fluid box5. The supply flow passage 47 branches into the plurality of upstreamflow passages 48 inside the fluid box 5. Each upstream flow passage 48can thus be reduced in length (length in a direction in which the liquidflows) in comparison to a case where the supply flow passage 47 branchesinto the plurality of upstream flow passages 48 at a position furtherupstream than the fluid box 5. Temperature decrease of the processingliquid due to heat transfer from the processing liquid to each upstreamflow passage 48 can thereby be suppressed.

Also with the present preferred embodiment, the first discharge port 34Aand the second discharge port 34B are aligned in a plan view in theradial direction Dr. When the plurality of nozzles 26 of the same lengthare aligned in a horizontal direction orthogonal to the longitudinaldirection D1 so that the plurality of discharge ports 34 are aligned ina plan view in the radial direction Dr, an entirety of the plurality ofnozzles 26 increases in width (see FIG. 9). When the plurality ofnozzles 26 of different lengths are aligned in a vertical direction sothat the plurality of discharge ports 34 are aligned in a plan view inthe radial direction Dr, the entirety of the plurality of nozzles 26increases in height (see FIG. 10A and FIG. 10B).

On the other hand, with the present preferred embodiment, the pluralityof arm portions 28 are aligned in the horizontal alignment direction D2orthogonal to the longitudinal direction D1. Further, the tips 28 a ofthe plurality of arm portions 28 are shifted in the longitudinaldirection D1 such that, in regard to the longitudinal direction D1, thetips 28 a of the plurality of arm portions 28 are aligned in the orderof the first nozzle 26A to the fourth nozzle 26D from the rotationalaxis A1 side (see FIG. 4). The plurality of discharge ports 34 canthereby be aligned in the radial direction Dr in a plan view whilesuppressing both the width and the height of the entirety of theplurality of nozzles 26.

The present invention is not restricted to the content of the preferredembodiment and various modifications are possible within the scope ofthe present invention.

For example, although with the preferred embodiment described above, thecase where the number of the nozzles 26 is four was described, thenumber of the nozzles 26 may be two or three or may be five or more.

Although with the preferred embodiment, the case where the chemicalliquid flowing through each of the return flow passages 54 toward thechemical tank 41 is cooled by the cooler 56 was described, the cooler 56may be omitted.

Although with the preferred embodiment, the case where, during dischargestoppage, the liquids heated by the downstream heaters 53 are made toflow from the upstream flow passages 48 to the return flow passages 54was described, if the downstream heaters 53 are to be stopped duringdischarge stoppage, the return flow passages 54 may be omitted.

Although with the preferred embodiment, the case where a downstreamheater 53 is not disposed at the first upstream flow passage 48A whiledownstream heaters 53 are disposed at all upstream flow passages 48besides the first upstream flow passage 48A was described, thedownstream heaters 53 may be disposed at all upstream flow passages 48including the first upstream flow passage 48A. Oppositely, thedownstream heaters 53 do not have to be disposed at all of the upstreamflow passages 48. The same applies to the return passages 54.

Although with the preferred embodiment, the case where a nozzle head 33is not disposed at the first nozzle 26A while nozzle heads 33 aremounted on all nozzles 26 besides the first nozzle 26A was described,the nozzle heads 33 may be disposed at all nozzles 26 including thefirst nozzle 26A. Oppositely, the nozzle heads 33 do not have to bedisposed at all of the nozzles 26.

Although with the preferred embodiment, the case where three downstreamflow passages 52 and three discharge ports 34 are defined in a singlenozzle head 33 was described, the number of downstream flow passages 52and discharge ports 34 defined in a single nozzle head 33 may be two ormay be four or more.

Although with the preferred embodiment, the case where each of thebranching upstream flow passages (the upstream flow passages 48 besidesthe first upstream flow passage 48A) branches into a plurality of thedownstream flow passages 52 within the chamber 7 was described, thebranching upstream flow passages may branch outside the chamber 7instead.

Although with the preferred embodiment, the case where the plurality ofdischarge ports 34 are aligned in the radial direction Dr in a plan viewwas described, as long as the plurality of discharge ports 34 arerespectively disposed at positions differing in distance from therotational axis A1, the plurality of discharge ports 34 do not have tobe aligned in the radial direction Dr in a plan view.

Although with the preferred embodiment, the case where each dischargeport 34 discharges the processing liquid in the discharge directionperpendicular to the upper surface of the substrate W was described, theplurality of discharge ports 34 may include an oblique discharge port 34x that discharges the processing liquid in a discharge direction that isinclined with respect to the upper surface of the substrate W so as toapproach the rotational axis A1 as the upper surface of the substrate Wis approached. FIG. 11 shows an example where an inner discharge portthat is positioned closest to the rotational axis A1 side among theplurality of discharge ports 34 disposed in the nozzle head 33 is theoblique discharge port 34 x.

With this arrangement, the processing liquid discharged from the obliquedischarge port 34 x has kinetic energy of a direction directed towardthe rotational axis A1 and therefore flows along the upper surface ofthe substrate W toward the rotational axis A1. Thereafter, theprocessing liquid flows toward the outer side along the upper surface ofthe substrate W due to the centrifugal force due to rotation of thesubstrate W and is expelled from the upper surface of the substrate W. Aretention time of the processing liquid on the substrate W is thusincreased in comparison to a case where the processing liquid isdischarged in a direction perpendicular to the upper surface of thesubstrate W or in a case where it is discharged in a direction that isoutwardly inclined with respect to the upper surface of the substrate W.The processing liquid can thus be used efficiently and the consumptionamount of the processing liquid can be reduced.

Although with the preferred embodiment, the case where the plurality ofnozzles 26 are made to discharge the chemical liquids while keeping theplurality of nozzles 26 still was described, the plurality of nozzles 26may be made to discharge the chemical liquids while making the pluralityof nozzles 26 pivot around the nozzle pivoting axis A2.

Although with the preferred embodiment, the case where all of thedischarge valves 51 are opened at the same time and all of the dischargevalves 51 are closed at the same time was described, the controller 3may control the plurality of discharge valves 51 so that the time duringwhich a discharge port 34 at an outer side is discharging the processingliquid is longer than the time during which a discharge port 34 at aninner side is discharging the processing liquid.

For example, as shown in FIG. 12, the controller 3 may make theplurality of nozzles 26 discharge the processing liquids in the order ofthe fourth nozzle 26D to the first nozzle 26A and thereafter stop thedischarges of processing liquid by the plurality of nozzles 26 at thesame time. Specifically, the controller 3 may successively open the fourdischarge valves 51 in the order of the fourth discharge valve 51 to thefirst discharge valve 51 and thereafter close the four discharge valves51 at the same time. In this case, the time of supplying of theprocessing liquid to each portion of the upper surface of the substrateW increases stepwise with distance away from the central portion of thesubstrate W.

If the processing liquid is discharged from just a single discharge port34, an etching rate tends to decrease with distance away from thecentral portion of the substrate W. Therefore, by increasing theprocessing liquid supplying time with distance away from the centralportion of the substrate W, the etching amounts at positions besides thecentral portion of the substrate W can be increased. The processinguniformity can thereby be increased.

Also, as shown in FIG. 13, the processing unit 2 may further include adischarge position adjusting unit 58 that moves the plurality ofdischarge ports 34 in a horizontal adjusting direction (the longitudinaldirection D1 in FIG. 13) that differs from the direction of movement ofthe plurality of discharge ports 34 by the nozzle moving unit 24. Thedischarge position adjusting unit 58 is held by the holder 25. Thedischarge position adjusting unit 58 moves the plurality of nozzles 26in the longitudinal direction D1 with respect to the holder 25. Theplurality of discharge position adjusting unit 58 may be a pneumaticactuator or an electric actuator or an actuator besides these.

With this arrangement, the nozzle moving unit 24 moves the plurality ofdischarge ports 34 and the discharge position adjusting unit 34horizontally. At the processing position, the plurality of dischargeports 34 are respectively disposed at the plurality of positionsdiffering in distance from the rotational axis A1. When the dischargeposition adjusting unit 58 moves the plurality of discharge ports 34 inthe adjusting direction, all of the discharge ports 34 are either movedcloser to or further away from the rotational axis A1 and the liquidlanding positions of the processing liquids with respect to the uppersurface of the substrate W are moved. An etching profile(cross-sectional shape of the upper surface of the substrate W afteretching) can be adjusted by making the discharge position adjusting unit58 move the plurality of discharge ports 34.

Although with the preferred embodiment, the case where the chemicalliquid flow passage 42 that supplies the chemical liquid to the supplyflow passage 47 is provided was described, a plurality of processingliquid flow passages that supply liquids to the supply flow passage 47may be provided.

For example, a first liquid may be supplied from a first liquid flowpassage to the supply flow passage 47 and a second liquid may besupplied from a second liquid flow passage to the supply flow passage47. In this case, the first liquid and the second liquid are mixed inthe supply flow passage 47 and therefore a mixed liquid containing thefirst liquid and the second liquid is supplied from the supply flowpassage 47 to the plurality of upstream flow passages 48. The firstliquid and the second liquid may be liquids of the same type or may beliquids of different types. Specific examples of the first liquid andthe second liquid include a combination of sulfuric acid and hydrogenperoxide water and a combination of TMAH and pure water.

The controller 3 may control the temperatures of the processing liquidssupplied to respective portions of the front surface of the substrate Win accordance with a thickness of a thin film before processing to makeuniform the thickness of the thin film after processing.

FIG. 14 is a graph showing a conceptual image of a thickness of a thinfilm before and after processing and a temperature of a processingliquid supplied to a substrate W. An alternate long and short dashesline in FIG. 14 indicates the film thickness before processing and analternate long and two short dashes line in FIG. 14 indicates the filmthickness after processing. A solid line in FIG. 14 indicates thetemperatures of the processing liquids supplied to the substrate W. Theabscissa axis of FIG. 14 indicates the radius of the substrate W. Thefilm thickness before processing may be input into the substrateprocessing apparatus 1 from an apparatus (for example, a host computer)other than the substrate processing apparatus 1 or may be measured by ameasuring instrument provided in the substrate processing apparatus 1.

With the example shown in FIG. 14, the controller 3 may control thesubstrate processing apparatus 1 so that the temperatures of theprocessing liquids vary similarly to the film thickness beforeprocessing. Specifically, the controller 3 may control the plurality ofdownstream heaters 53 so that the temperatures of the processing liquidsin the plurality of upstream flow passages 48 are temperatures that arein accordance with the film thickness before processing.

In this case, processing liquid of relatively high temperature issupplied to a position at which the film thickness before processing isrelatively large and processing liquid of relatively low temperature issupplied to a position at which the film thickness before processing isrelatively small. The etching amount of the thin film formed on thefront surface of the substrate W increases relatively at a position atwhich processing liquid of high temperature is supplied and decreasesrelatively at a position at which processing liquid of low temperatureis supplied. The thin film is thus made uniform in thickness afterprocessing.

Two or more of any of the arrangements described above may be combined.Two or more of any of the processes described above may be combined.

Second Preferred Embodiment

A second preferred embodiment of the present invention shall now bedescribed. Components equivalent to the respective portions describedabove shall be provided with the same reference symbols as in FIG. 1,etc., and description thereof shall be omitted.

When the substrate W is to be processed by the processing unit 2, thesubstrate W is carried into the interior of the chamber 7 by the hand(not shown) of the transfer robot in the state where the plurality ofnozzles 26 are retracted from above the spin chuck 11 and the splashguard 17 is positioned at the lower position. The substrate W is therebyplaced, in the state where the front surface is faced up, on theplurality of chuck pins 13. Thereafter, the hand of the transfer robotis retracted from the interior of the chamber 7 and thecarry-in/carry-out port 8 a of the chamber 7 is closed by the shutter 9.

After the substrate W has been placed on the plurality of chuck pins 13,the plurality of chuck pins 13 are pressed against the peripheral edgeportions of the substrate W and the substrate W is gripped by theplurality of chuck pins 13. Also, the guard raising/lowering unit 18moves the splash guard 17 from the lower position to the upper position.The upper end of the splash guard 17 is thereby disposed higher than thesubstrate W. Thereafter, the spin motor 14 is driven to start rotationof the substrate W. The substrate W is thereby rotated at apredetermined liquid processing speed (of, for example, several hundredrpm).

Thereafter, the nozzle moving unit 24 moves the plurality of nozzles 26from the standby position to the processing position. The plurality ofdischarge ports 34 are thereby overlapped with the substrate W in a planview. Thereafter, the plurality of discharge valves 51, etc., arecontrolled and the chemical liquids are discharged at the same time fromthe plurality of nozzles 26 (step S1 of FIG. 7). The plurality ofnozzles 26 discharge the chemical liquids in a state where the nozzlemoving unit 24 swings the plurality of nozzles 26 around the rotationalaxis A1 (in regard to the swinging, see the alternate long and two shortdashes lines in FIG. 15). When a predetermined time elapses from theopening of the plurality of discharge valves 51, the discharges ofchemical liquids from the plurality of nozzles 26 are stopped at thesame time (step S2 of FIG. 7). Thereafter, the nozzle moving unit 24moves the plurality of nozzles 26 from the processing position to thestandby position.

The chemical liquids discharged from the plurality of nozzles 26 land onthe upper surface of the rotating substrate W and thereafter flowoutward (in the direction away from the rotational axis A1) along theupper surface of the substrate W due to the centrifugal force. Thechemical liquid that reaches the upper surface peripheral edge portionof the substrate W is scattered to a periphery of the substrate W andreceived by the inner peripheral surface of the splash guard 17. Thechemical liquid is thereby supplied to the entire upper surface of thesubstrate W and the liquid film of chemical liquid that covers theentire upper surface of the substrate W is formed on the substrate W.The entire upper surface of the substrate W is thereby processed by thechemical liquid.

After the discharges of chemical liquids from the plurality of nozzles26 have been stopped, the rinse liquid valve 23 is opened and dischargeof the rinse liquid (pure water) from the rinse liquid nozzle 21 isstarted (step S3 of FIG. 7). The chemical liquid on the substrate W isthereby rinsed off by the rinse liquid and the liquid film of rinseliquid that covers the entire upper surface of the substrate W isformed. When a predetermined time elapses from the opening of the rinseliquid valve 23, the rinse liquid valve 23 is closed and the dischargeof the rinse liquid from the rinse liquid nozzle 21 is stopped (step S4of FIG. 7).

After the discharge of the rinse liquid from the rinse liquid nozzle 21has been stopped, the substrate W is accelerated in the rotationaldirection by the spin motor 14 and the substrate W is rotated at adrying speed (of, for example, several thousand rpm) higher than theliquid processing speed (step S5 of FIG. 7). The rinse liquid attachedto the substrate W is thereby spun off to the periphery of the substrateW and the substrate W is dried. When a predetermined time elapses fromthe start of high speed rotation of the substrate W, the rotation of thespin motor 14 and the substrate W is stopped.

After the rotation of the substrate W has been stopped, the guardraising/lowering unit 18 moves the splash guard 17 from the upperposition to the lower position. Further, the holding of the substrate Wby the plurality of chuck pins 13 is released. The transfer robot makesits hand enter the interior of the chamber 7 in the state where theplurality of nozzles 26 are retracted from above the spin chuck 11 andthe splash guard 17 is positioned at the lower position. Thereafter, thetransfer robot uses the hand to take the substrate W on the spin chuck11 and carries out the substrate W from the chamber 7.

FIG. 16 is a graph of etching amount distributions of substrates W.

The processing conditions of the substrates W of measurement A tomeasurement C shown in FIG. 16 are the same with the exception of thenozzles that discharge the chemical liquids.

The measurement A indicates the etching amount distribution when asubstrate W is etched by making a plurality of discharge ports 34 (tendischarge ports 34) discharge the chemical liquids while keeping stillthe plurality of nozzles 26.

The measurement B indicates the etching amount distribution when asubstrate W is etched by making a plurality of discharge ports 34 (fourdischarge ports 34) discharge the chemical liquids while keeping stillthe plurality of nozzles 26 from which all nozzle heads 33 have beenremoved. That is, the measurement B indicates the etching amountdistribution when the four discharge ports 34 (corresponding to thefirst discharge port 34A) respectively disposed in the four main nozzlebodies 27 are made to discharge the chemical liquids.

The measurement C indicates the etching amount distribution when just asingle discharge port 34 is made to discharge the chemical liquid andthe liquid landing position of the chemical liquid is fixed at the uppersurface central portion of the substrate W.

With the measurement C, the etching amount decreases with distance awayfrom the central portion of the substrate W and the etching amountdistribution exhibits a peak-shaped curve. That is, the etching amountis greatest at the liquid landing position of the chemical liquid anddecreases with distance away from the liquid landing position. On theother hand, with the measurement A and the measurement B, the etchingamounts at positions besides the central portion of the substrate W areincreased and the etching uniformity is greatly improved in comparisonto the measurement C.

With the measurement B, seven peaks are formed. The apex of the centralpeak is at a position corresponding to the innermost liquid landingposition and the apexes of the two peaks at outer sides thereof are atpositions corresponding to the second liquid landing position from theinner side. The positions of the apexes of the two peaks further to theouter sides are positions corresponding to the third liquid landingposition from the inner side, and the positions of the two outermostpeaks are positions corresponding to the fourth liquid landing positionfrom the inner side.

With the measurement A, a plurality of peaks corresponding to theplurality of liquid landing positions are formed similarly to themeasurement B. Whereas with the measurement B, the number of dischargeports 34 is four, with the measurement A, the number of discharge ports34 is ten and therefore the number of peaks is increased. Further incomparison to the measurement B, the curve indicating the etching amountdistribution is closer to being the straight line extending in theright/left direction (the straight line of fixed etching amount) and theetching uniformity is improved.

As mentioned above, the nozzle moving unit 24 swings the plurality ofnozzles 26 around the nozzle pivoting axis A2 within a range in whichthe chemical liquids discharged from the plurality of discharge ports 34land on the upper surface of the substrate W. In this process, eachdischarge port 34 reciprocates horizontally once or more along anarcuate path with a center on the nozzle rotational axis A2. Thedistances from the rotational axis A1 to the respective discharge ports34 are thus changed.

The measurement A and the measurement B indicate etching amountdistributions when the substrates W are etched with the plurality ofnozzles 26 being kept still. When the nozzle moving unit 24 swings theplurality of nozzles 26, the liquid landing positions move in the radialdirection Dr and the line indicating the etching amount distribution ismade even closer to being the straight line extending in the right/leftdirection (the straight line of fixed etching amount). The etchinguniformity can thereby be increased further.

With the second preferred embodiment, the following actions and effectscan be exhibited in addition to the actions and effects according to thefirst preferred embodiment.

Also with the present preferred embodiment, the nozzle moving unit 24swings the plurality of discharge ports 34 in the state where thesubstrate W is rotating and the plurality of discharge ports 34 aredischarging the chemical liquids. The distanced from the rotational axisA1 to the respective discharge ports 34 are thereby changed. Thechemical liquids discharged from the plurality of discharge ports 34land on the plurality of liquid landing positions within the uppersurface of the substrate W. The etching amount of the substrate W isgreatest at each liquid landing position and decreases with distanceaway from the liquid landing position. The plurality of discharge ports34 are moved horizontally and the plurality of liquid landing positionsare also moved within the upper surface of the substrate W accordingly.The processing uniformity can thereby be increased in comparison to acase where the plurality of discharge ports 34 are not moved.

Also with the present preferred embodiment, the processing liquids thathave been heated at the downstream temperatures higher than the upstreamtemperature by the downstream heaters 53 are supplied to the dischargeports 34 besides the innermost discharge port (first discharge port 34A)from the upstream flow passages 48 besides the innermost upstream flowpassage (first upstream flow passage 48A) and are discharged from thedischarge ports 34. That is, whereas the processing liquid of theupstream temperature is discharged from the innermost discharge port,the processing liquid of higher temperature than the upstreamtemperature is discharged from each of the discharge ports 34 positionedfurther to the outer side than the innermost discharge port.

The temperatures of the processing liquids supplied to the upper surfaceof the substrate W thus increase stepwise with distance away from therotational axis A1 and the temperature uniformity can thus be increasedin comparison to the case where the processing liquid of the sametemperature is discharged from each discharge port 34. The processinguniformity can thus be increased while reducing the consumption amountof the processing liquid.

The present invention is not restricted to the content of the preferredembodiment and various modifications are possible within the scope ofthe present invention.

For example, although the case where the chemical liquid flow passage 42that supplies the chemical liquid to the supply flow passage 47 isprovided was described, a plurality of processing liquid flow passagesthat supply liquids to the supply flow passage 47 may be provided.

For example, a first liquid may be supplied from a first liquid flowpassage to the supply flow passage 47 and a second liquid may besupplied from a second liquid flow passage to the supply flow passage47. In this case, the first liquid and the second liquid are mixed inthe supply flow passage 47 and therefore a mixed liquid containing thefirst liquid and the second liquid is supplied from the supply flowpassage 47 to the plurality of upstream flow passages 48. The firstliquid and the second liquid may be liquids of the same type or may beliquids of different types. Specific examples of the first liquid andthe second liquid include a combination of sulfuric acid and hydrogenperoxide water and a combination of TMAH and pure water.

Two or more of any of the arrangements described above may be combined.Two or more of any of the processes described above may be combined.

Third Preferred Embodiment

A third preferred embodiment of the present invention shall now bedescribed. Components equivalent to the respective portions describedabove shall be provided with the same reference symbols as in FIG. 1,etc., and description thereof shall be omitted.

The substrate processing apparatus 1 includes a gas supplying unit thatdischarges a high temperature gas toward the substrate W to heat theliquid on the substrate W. As shown in FIG. 17 and FIG. 18, the gassupplying unit includes a plurality of gas nozzles 82 (first gas nozzle82A, second gas nozzle 82B, and third gas nozzle 82C) provided with aplurality of gas discharge ports 81 that discharge a gas downward. Anexample of the gas is nitrogen gas. The gas may be an inert gas besidesnitrogen gas or may be clean air filtered by a filter or may be a gasbesides the above.

As shown in FIG. 17, the gas supplying unit includes a gas piping 83guiding the gas to the plurality of gas nozzles 82, a gas heater 84heating the gas, flowing through the gas piping 83 toward the pluralityof gas discharge ports 81, at a temperature higher than roomtemperature, and a gas valve 85 opening and closing the gas piping 83.The temperature of heating of the gas by the gas heater 84 is higherthan room temperature and lower than the boiling point of the chemicalliquid.

The first gas nozzle 82A to the third gas nozzle 82C are respectivelyheld by the first nozzle 26A to the third nozzle 26C. The gas nozzles 82move together with the nozzles 26. The plurality of nozzles 26 and theplurality of gas nozzles 82 are aligned alternately in regard to theradial direction Dr. The plurality of discharge ports 34 and theplurality of gas discharge ports 81 are aligned in the radial directionDr in a plan view. The first discharge port 34A is disposed further tothe inner side than the innermost gas discharge port 81 and the seconddischarge port 34B is disposed further to the outer side than theinnermost gas discharge port 81. The plurality of discharge ports 34 andthe plurality of gas discharge ports 81 are shifted in position so that,in regard to the radial direction Dr, a gas discharge port 81 ispositioned between two adjacent discharge ports 34.

The plurality of gas nozzles 82 discharge the gas toward a plurality ofblowing-on positions P1 to P3 within the upper surface of the substrateW. The plurality of blowing-on positions P1 to P3 are separate positionsthat respectively differ in distance from the rotational axis A1. InFIG. 17, the liquid landing positions at which the chemical liquids landare indicated by “x.” The plurality of liquid landing positionsrespectively corresponding to the plurality of second discharge ports34B are positioned between the innermost blowing-on position P1 and themiddle blowing-on position P2 in regard to the radial direction Dr. Theplurality of liquid landing positions respectively corresponding to theplurality of third discharge ports 34C are positioned between the middleblowing-on position P2 and the outermost blowing-on position P3 inregard to the radial direction Dr.

FIG. 19 is a process flowchart for describing an example of processingof the substrate W executed by the substrate processing apparatus 1. Therespective operations described below are executed by the controller 3controlling the substrate processing apparatus 1. FIG. 3 and FIG. 4shall be referenced in the following description. FIG. 17 and FIG. 19shall be referenced where suitable.

When the substrate W is to be processed by the processing unit 2, thesubstrate W is carried into the interior of the chamber 7 by the hand(not shown) of the transfer robot in the state where the plurality ofnozzles 26 are retracted from above the spin chuck 11 and the splashguard 17 is positioned at the lower position. The substrate W is therebyplaced, in a state where the front surface is faced up, on the pluralityof chuck pins 13. Thereafter, the hand of the transfer robot isretracted from the interior of the chamber 7 and the carry-in/carry-outport 8 a of the chamber 7 is closed by the shutter 9.

After the substrate W has been placed on the plurality of chuck pins 13,the plurality of chuck pins 13 are pressed against the peripheral edgeportions of the substrate W and the substrate W is gripped by theplurality of chuck pins 13. Also, the guard raising/lowering unit 18moves the splash guard 17 from the lower position to the upper position.The upper end of the splash guard 17 is thereby disposed higher than thesubstrate W. Thereafter, the spin motor 14 is driven to start rotationof the substrate W. The substrate W is thereby rotated at apredetermined liquid processing speed (of, for example, several hundredrpm).

Thereafter, the nozzle moving unit 24 moves the plurality of nozzles 26from the standby position to the processing position. The plurality ofdischarge ports 34 are thereby overlapped with the substrate W in a planview. Thereafter, the plurality of discharge valves 51, etc., arecontrolled and the chemical liquids are discharged at the same time fromthe plurality of nozzles 26 (step S1 of FIG. 19). The plurality ofnozzles 26 discharge the chemical liquids in a state where the nozzlemoving unit 24 keeps the plurality of nozzles 26 still. When apredetermined time elapses from the opening of the plurality ofdischarge valves 51, the discharges of chemical liquids from theplurality of nozzles 26 are stopped at the same time (step S2 of FIG.19). Thereafter, the nozzle moving unit 24 moves the plurality ofnozzles 26 from the processing position to the standby position.

The chemical liquids discharged from the plurality of nozzles 26 land onthe upper surface of the rotating substrate W and thereafter flowoutward (in the direction away from the rotational axis A1) along theupper surface of the substrate W due to the centrifugal force. Thechemical liquid that reaches the upper surface peripheral edge portionof the substrate W is scattered to the periphery of the substrate W andreceived by the inner peripheral surface of the splashguard 17. Thechemical liquid is thereby supplied to the entire upper surface of thesubstrate W and the liquid film of chemical liquid that covers theentire upper surface of the substrate W is formed on the substrate W.The entire upper surface of the substrate W is thereby processed by thechemical liquid.

Also, when the plurality of nozzles 26 are disposed at the processingposition, the gas valve 85 (see FIG. 17) is opened and the hightemperature gas, such as nitrogen gas, etc., is discharged from the gasdischarge ports 81 of the plurality of gas nozzles 82. The hightemperature gas is thereby blown onto the liquid film of chemical liquidthat covers the entire upper surface of the substrate W. When apredetermined time elapses from the opening of the gas valve 85, the gasvalve 85 is closed and the discharge of gas from the plurality of gasnozzles 82 is stopped. As long as at least a portion of the gasdischarging period overlaps with the chemical liquid discharging period,the discharge of the gas may be started at the same time as thedischarges of the chemical liquids or may be started before or after thedischarges of the chemical liquids. The same applies to dischargestoppage of the gas.

After the discharges of chemical liquids from the plurality of nozzles26 have been stopped, the rinse liquid valve 23 is opened and dischargeof the rinse liquid (pure water) from the rinse liquid nozzle 21 isstarted (step S3 of FIG. 19). The chemical liquid on the substrate W isthereby rinsed off by the rinse liquid and the liquid film of rinseliquid that covers the entire upper surface of the substrate W isformed. When a predetermined time elapses from the opening of the rinseliquid valve 23, the rinse liquid valve 23 is closed and the dischargeof the rinse liquid from the rinse liquid nozzle 21 is stopped (step S4of FIG. 19).

After the discharge of the rinse liquid from the rinse liquid nozzle 21has been stopped, the substrate W is accelerated in the rotationaldirection by the spin motor 14 and the substrate W is rotated at adrying speed (of, for example, several thousand rpm) higher than theliquid processing speed (step S5 of FIG. 19). The rinse liquid attachedto the substrate W is thereby spun off to the periphery of the substrateW and the substrate W is dried. When a predetermined time elapses fromthe start of high speed rotation of the substrate W, the rotation of thespin motor 14 and the substrate W is stopped.

After the rotation of the substrate W has been stopped, the guardraising/lowering unit 18 moves the splash guard 17 from the upperposition to the lower position. Further, the holding of the substrate Wby the plurality of chuck pins 13 is released. The transfer robot makesits hand enter the interior of the chamber 7 in the state where theplurality of nozzles 26 are retracted from above the spin chuck 11 andthe splash guard 17 is positioned at the lower position. Thereafter, thetransfer robot uses the hand to take the substrate W on the spin chuck11 and carries out the substrate W from the chamber 7.

FIG. 20 is a graph of etching amount distributions of substrates W.

The processing conditions of the substrates W of measurement A tomeasurement C shown in FIG. 20 are the same with the exception of thenozzles that discharge the chemical liquids.

The measurement A indicates the etching amount distribution when asubstrate W is etched by making a plurality of discharge ports 34 (tendischarge ports 34) discharge the chemical liquids while keeping stillthe plurality of nozzles 26.

The measurement B indicates the etching amount distribution when asubstrate W is etched by making a plurality of discharge ports 34 (fourdischarge ports 34) discharge the chemical liquids while keeping stillthe plurality of nozzles 26 from which all nozzle heads 33 have beenremoved. That is, the measurement B indicates the etching amountdistribution when the four discharge ports 34 (corresponding to thefirst discharge port 34A) respectively disposed in the four main nozzlebodies 27 are made to discharge the chemical liquids.

The measurement C indicates the etching amount distribution when just asingle discharge port 34 is made to discharge the chemical liquid andthe liquid landing position of the chemical liquid is fixed at the uppersurface central portion of the substrate W.

With the measurement C, the etching amount decreases with distance awayfrom the central portion of the substrate W and the etching amountdistribution exhibits a peak-shaped curve. That is, the etching amountis greatest at the liquid landing position of the chemical liquid anddecreases with distance away from the liquid landing position. On theother hand, with the measurement A and the measurement B, the etchingamounts at positions besides the central portion of the substrate W areincreased and the etching uniformity is greatly improved in comparisonto the measurement C.

With the measurement B, seven peaks are formed. The apex of the centralpeak is at a position corresponding to the innermost liquid landingposition and the apexes of the two peaks at outer sides thereof are atpositions corresponding to the second liquid landing position from theinner side. The positions of the apexes of the two peaks further to theouter sides are positions corresponding to the third liquid landingposition from the inner side, and the positions of the two outermostpeaks are positions corresponding to the fourth liquid landing positionfrom the inner side.

With the measurement A, a plurality of peaks corresponding to theplurality of liquid landing positions are formed similarly to themeasurement B. Whereas with the measurement B, the number of dischargeports 34 is four, with the measurement A, the number of discharge ports34 is ten and therefore the number of peaks is increased. Further incomparison to the measurement B, the curve indicating the etching amountdistribution is closer to being the straight line extending in theright/left direction (the straight line of fixed etching amount) and theetching uniformity is improved.

With the processing of the substrates W for the measurement A to themeasurement C, the discharge of gas from the gas nozzles 82 is notperformed. As mentioned above, the controller 3 makes the plurality ofgas discharge ports 81 discharge the high temperature gas in the statewhere the plurality of discharge ports 34 are discharging the chemicalliquids toward the upper surface of the rotating substrate W. The hightemperature gas is thereby blown onto the liquid film of the chemicalliquid covering the entire upper surface of the substrate W.

The gas discharge ports 81 discharge the gas toward the blowing-onpositions P1 to P3 (see FIG. 17) within the upper surface of thesubstrate W. Each of the blowing-on positions P1 to P3 is a positionbetween two liquid landing positions in the radial direction Dr.Therefore as indicated by arrows in FIG. 20, temperature decrease of thechemical liquid is suppressed or prevented at positions, each locatedbetween two liquid landing positions, and improvement is made in regardto the decrease of etching amount at such positions. The curveindicating the etching amount distribution is thereby made even closerto being the straight line extending in the right/left direction (thestraight line of fixed etching amount) and the etching uniformity isincreased.

With the third preferred embodiment, the following actions and effectscan be exhibited in addition to the actions and effects according to thefirst preferred embodiment.

With the present preferred embodiment, the gas discharge ports 81discharge the gas toward blowing-on positions P1 to P3 within the uppersurface of the substrate W in a state where the upper surface of thesubstrate W is covered with the liquid film of the chemical liquid. Adischarge pressure of the gas is a pressure such that the blowing-onpositions P1 to P3 do not become exposed from the chemical liquid. Thedischarged gas is a high temperature gas of higher temperature than roomtemperature. Therefore, by the supplying of the gas, an improvement canbe made in regard to the temperature decrease of the chemical liquid onthe substrate W. Further, the plurality of gas discharge ports 91 arerespectively disposed at the plurality of positions differing indistance from the rotational axis A1 and the chemical liquid on thesubstrate W can thus be heated at the plurality of positions that areseparated in the radial direction Dr. The temperature uniformity of thechemical liquid can thereby be increased.

Also with the present preferred embodiment, the plurality of liquidlanding positions and the plurality of blowing-on positions P1 to P3 arenot aligned in the circumferential direction (the direction around therotational axis A1) but are shifted in the radial direction Dr. Theetching amount of the substrate W decreases with distance away from aliquid landing position and is the smallest at an intermediate positionbetween two liquid landing positions in the radial direction Dr. Each ofthe blowing-on positions P1 to P3 is a position between two liquidlanding positions in the radial direction Dr. Temperature decrease ofthe chemical liquid at a position between two liquid landing positionsis thus suppressed or prevented and improvement is achieved in regard tothe decrease of the etching amount at this position. The processinguniformity is thereby increased.

Also with the present preferred embodiment, the processing liquids thathave been heated at the downstream temperatures higher than the upstreamtemperature by the downstream heaters 53 are supplied to the dischargeports 34, besides the innermost discharge port (the first discharge port34A), from the upstream flow passages 48 besides the innermost upstreamflow passage (the first upstream flow passage 48A) and are dischargedfrom the discharge ports 34. That is, whereas the processing liquid ofthe upstream temperature is discharged from the innermost dischargeport, the processing liquid of higher temperature than the upstreamtemperature is discharged from each of the discharge ports 34 positionedfurther to the outer side than the innermost discharge port.

The temperatures of the processing liquids supplied to the upper surfaceof the substrate W thus increase stepwise with distance away from therotational axis A1 and the temperature uniformity can thus be increasedin comparison to the case where the processing liquid of the sametemperature is discharged from each discharge port 34. The processinguniformity can thereby be increased while reducing the consumptionamount of the processing liquid.

The present invention is not restricted to the content of the preferredembodiment and various modifications are possible within the scope ofthe present invention.

For example, although with the preferred embodiment described above, thecase where the number of the nozzles 26 is four was described, thenumber of the nozzles 26 may be two or three or may be five or more. Thesame applies to the gas nozzles 82.

Although with the preferred embodiment, the case where the plurality ofdischarge ports 34 and the plurality of gas discharge ports 81 arealigned in the radial direction Dr in a plan view was described, theplurality of gas discharge ports 81 may be shifted in thecircumferential direction with respect to the plurality of dischargeports 34. Also, as long as the plurality of discharge ports 34 arerespectively disposed at a plurality of positions differing in distancefrom the rotational axis A1, the plurality of discharge ports 34 do nothave to be aligned in the radial direction Dr in a plan view. The sameapplies to the gas discharge ports 81.

The substrate processing apparatus 1 may include, in addition to or inplace of the gas supplying unit, a chamber temperature raising unit thatraises the atmospheric temperature inside the chamber 7. The chambertemperature raising unit may be a heater that heats the gas inside thechamber 7 or a fan that feeds a gas of higher temperature than roomtemperature into the chamber 7. In this case, temperature decrease ofthe processing liquid on the substrate W is suppressed or preventedbecause the atmospheric temperature inside the chamber 7 increases. Animprovement can thereby be made in regard to the temperature decrease ofthe processing liquid on the substrate W to increase the processinguniformity.

The substrate processing apparatus 1 may include, in addition to or inplace of the gas supplying unit, a light emitting unit that emits lighttoward the upper surface of the substrate W held by the spin chuck 11 toheat the processing liquid on the substrate W. The light emitting unitmay be an infrared irradiation unit (for example, an infrared heater)that emits infrared rays or a laser irradiation unit that emits a laser.

The light emitting unit emits light toward a plurality of irradiationpositions within the upper surface of the substrate W in a state wherethe upper surface of the substrate W is covered by the liquid film ofthe processing liquid. The plurality of liquid landing positions and theplurality of irradiation positions are preferably shifted in regard tothe radial direction Dr so that an irradiation position is positionedbetween two adjacent liquid landing positions. Temperature decrease ofthe processing liquid on the substrate W is suppressed by theirradiation of light. Further, the plurality of irradiation positionsare separate positions that respectively differ in distance from therotational axis A1, and the processing liquid on the substrate W canthus be heated at a plurality of positions separated in the radialdirection Dr. The temperature uniformity of the processing liquid canthereby be increased.

Although with the preferred embodiment, the case where the chemicalliquid flow passage 42 that supplies the chemical liquid to the supplyflow passage 47 is provided was described, a plurality of processingliquid flow passages that supply liquids to the supply flow passage 47may be provided.

For example, a first liquid may be supplied from a first liquid flowpassage to the supply flow passage 47 and a second liquid may besupplied from a second liquid flow passage to the supply flow passage47. In this case, the first liquid and the second liquid are mixed inthe supply flow passage 47 and therefore a mixed liquid containing thefirst liquid and the second liquid is supplied from the supply flowpassage 47 to the plurality of upstream flow passages 48. The firstliquid and the second liquid may be liquids of the same type or may beliquids of different types. Specific examples of the first liquid andthe second liquid include a combination of sulfuric acid and hydrogenperoxide water and a combination of TMAH and pure water.

Two or more of any of the arrangements described above may be combined.Two or more of any of the processes described above may be combined.

Fourth Preferred Embodiment

A fourth preferred embodiment of the present invention shall now bedescribed. Components equivalent to the respective portions describedabove shall be provided with the same reference symbols as in FIG. 1,etc., and description thereof shall be omitted.

As shown in FIG. 24, the processing unit 2 includes the plurality ofnozzles 26 (first nozzle 26A, second nozzle 26B, third nozzle 26C, andfourth nozzle 26D) that discharge the chemical liquids downward, theholder 25 that holds each of the plurality of nozzles 26, and the nozzlemoving unit 24 that moves the holder 25 to move the plurality of nozzles26 between the processing position (position indicated by alternate longand two short dashes lines in FIG. 24) and the standby position(position indicated by solid lines in FIG. 24).

Representative examples of the chemical liquid include etching liquids,such as TMAH, etc., and resist removing liquids, such as SPM, etc. Thechemical liquid is not restricted to TMAH and SPM, and may be a liquidcontaining at least one of sulfuric acid, acetic acid, nitric acid,hydrochloric acid, hydrofluoric acid, ammonia water, hydrogen peroxidewater, an organic acid, an organic alkali besides TMAH, a surfactant,and a corrosion inhibitor.

As shown in FIG. 23, each of the nozzles 26 includes the main nozzlebody 27 that is cantilevered by the holder 25 and a nozzle head 33 thatis shared with the other nozzles 26. The main nozzle body 27 includesthe arm portion 28 extending in the horizontal longitudinal direction D1from the holder 25 and the tip portion 29 extending downward from thetip 28 a of the arm portion 28. The tip 28 a of the arm portion 28 meansthe portion disposed furthest in the longitudinal direction D1 from theholder 25 in a plan view. The nozzle head 33 is supported by the tipportions 29 of the respective main nozzle bodies 29.

As shown in FIG. 24, the plurality of arm portions 28 are aligned in thehorizontal alignment direction D2, orthogonal to the longitudinaldirection D1, in the order of the first nozzle 26A to the fourth nozzle26D. The plurality of arm portions 28 are disposed at the same height.The interval between two arm portions 28 that are adjacent in thealignment direction D2 may be the same as any of the other intervals ormay differ from at least one of the other intervals. FIG. 24 shows anexample where the plurality of arm portions 28 are disposed at equalintervals.

The lengths of the plurality of arm portions 28 in the longitudinaldirection D1 decrease in the order of the first nozzle 26A to the fourthnozzle 26D. The tips of the plurality of nozzles 26 (the tips 28 a ofthe plurality of arm portions 28) are shifted in the longitudinaldirection D1 so as to be aligned in the order of the first nozzle 26A tothe fourth nozzle 26D in regard to the longitudinal direction D1. Thetips of the plurality of nozzles 26 are aligned rectilinearly in a planview.

The nozzle moving unit 24 makes the holder 25 pivot around the nozzlepivoting axis A2 extending vertically at the periphery of the cup 15 tomove the plurality of nozzles 26 along the arcuate path passing thesubstrate W in a plan view. The plurality of nozzles 26 are therebymoved horizontally between the processing position and the standbyposition. The processing unit 2 includes the bottomed cylindricalstandby pot 35 that is disposed below the standby position of theplurality of nozzles 26. The standby pot 35 is disposed at the peripheryof the cup 15 in a plan view.

The processing position is a position at which the chemical liquidsdischarged from the nozzle head 33 land on the upper surface of thesubstrate W. At the processing position, the nozzle head 33 and thesubstrate W overlap in a plan view and the tips of the plurality ofnozzles 26 are aligned in the radial direction Dr in the order of thefirst nozzle 26A to the fourth nozzle 26D from the rotational axis A1side in a plan view. In this state, the tip of the first nozzle 26Aoverlaps with the central portion of the substrate W in a plan view andthe tip of the fourth nozzle 26D overlaps with the peripheral edgeportion of the substrate W in a plan view.

The standby position is a position to which the plurality of nozzles 26are retracted so that the nozzle head 33 and the substrate W do notoverlap in a plan view. At the standby position, the tips of theplurality of nozzles 26, in a plan view, are positioned outside the cup15 and along the outer circumferential surface of the cup 15 (outercircumferential surface of the outer wall 16) and are aligned in thecircumferential direction (direction around the rotational axis A1) inthe order of the first nozzle 26A to the fourth nozzle 26D. Theplurality of nozzles 26 are disposed to be further away from therotational axis A1 in the order of the first nozzle 26A to the fourthnozzle 26D.

The plurality of nozzles 26 shall now be described with reference toFIG. 25 to FIG. 27. Thereafter, the processing liquid supplying systemshall be described. FIG. 25 to FIG. 27 show a state where the pluralityof nozzles 26 are disposed at the processing position.

In the following description, “first” and “A” may be added to thebeginning and the end of an arrangement corresponding to the firstnozzle 26A. For example, the upstream flow passage 48 associated withthe first nozzle 26A may be referred to as the “first upstream flowpassage 48A.” The same applies to arrangements associated with thesecond nozzle 26B to the fourth nozzle 26D.

Also in the following description, the temperature at which theprocessing liquid is heated by the upstream heater 43 may be referred toas the “upstream temperature” and the temperature at which theprocessing liquid is heated by the downstream heater 53 may be referredto as the “downstream temperature.” The temperatures at which theprocessing liquids are heated by the second downstream heater 53 to thefourth downstream heater 53 may be referred to respectively as the“second downstream temperature” to the “fourth heating temperature.”

As shown in FIG. 25, each main nozzle body 27 includes the resin tube 30that guides the processing liquid, the core bar 31 of cylindrical crosssection that surrounds the resin tube 30, and the resin coating 32 ofcylindrical cross section that surrounds the outer surface of the corebar 31. A lower surface of the resin tube 30 at which a discharge portis defined is disposed in an interior of the nozzle head 33.

Each main nozzle body 27 defines a single flow passage extending alongthe main nozzle body 27. The flow passage of the main nozzle body 27corresponds to a portion of the upstream flow passage 48 to be describedbelow. As shown in FIG. 26, downstream ends 48 d of the first upstreamflow passage 48A to the fourth upstream flow passage 48D arerespectively disposed at a plurality of positions differing in distancefrom the rotational axis A1 and are aligned in the radial direction Drin a plan view.

The downstream end 48 d of the first upstream flow passage 48A isdisposed further to the rotational axis A1 side than the downstream ends48 d of the second upstream flow passage 48B to the fourth upstream flowpassage 48D. The first upstream flow passage 48A is an example of a mainupstream flow passage and the second upstream flow passage 48B to thefourth upstream flow passage 48D are an example of a plurality ofauxiliary upstream flow passages. The downstream end 48 d of the firstupstream flow passage 48 is an example of a main downstream end and thedownstream ends 48 d of the second upstream flow passage 48B to thefourth upstream flow passage 48D are an example of a plurality ofdownstream ends.

As shown in FIG. 25, the nozzle head 33 defines a single flow passage(collective flow passage 52) that guides the processing liquids suppliedfrom the plurality of main nozzle bodies 27 and a slit-shaped slitdischarge port 34 opening at a lower surface of the nozzle head 33. Theslit discharge port 34 is parallel to the upper surface of the substrateW. The slit discharge port 34 is disposed below the downstream ends 48 dof the respective upstream flow passages 48A to 48D.

As shown in FIG. 26, the slit discharge port 34 extends, in a plan view,in the radial direction Dr from the upper surface central portion of thesubstrate W to the upper surface peripheral edge portion of thesubstrate W. A width W1 (the width means a length in a horizontaldirection orthogonal to the radial direction Dr; the same applieshereinafter) of the slit discharge port 34 is fixed from one end of theslit discharge port 34 to the other end of the slit discharge port 34.The width W1 of the slit discharge port 34 is smaller than a diameter ofeach of the downstream ends 48 d of the upstream flow passages 48A to48D. A portion of each of the downstream ends 48 d of the upstream flowpassages 48A to 48D overlaps with the slit discharge port 34 in a planview and the remaining portion does not overlap with the slit dischargeport 34 in a plan view. The slit discharge port 34 discharges thechemical liquids supplied from the collective flow passage 52perpendicularly toward the upper surface of the substrate W.

As shown in FIG. 27, the collective flow passage 52 connects thedownstream ends 48 d of the respective upstream flow passages 48A to 48Dto the slit discharge port 34. A width of the collective flow passage 52decreases continuously from an upstream end 52 u of the collective flowpassage 52 to a downstream end 52 d of the collective flow passage 52. Awidth W2 of the upstream end 52 u of the collective flow passage 52 isnot less than the diameter of each of the downstream ends 48 d of theupstream flow passages 48A to 48D. A width of the downstream end 52 d ofthe collective flow passage 52 is equal to the width W1 of the slitdischarge port 34.

A height of the collective flow passage 52, that is, a distance in thevertical direction from the downstream end 52 d of the collective flowpassage 52 to the upstream end 52 u of the collective flow passage 52 isgreater than the width W2 of the upstream end 52 u of the collectiveflow passage 52. A length of the collective flow passage 52 in theradial direction Dr is longer than the distance in the radial directionDr from the downstream end 48 d of the first upstream flow passage 48Ato the downstream end 48 d of the fourth upstream flow passage 48D.Respective ends of the collective flow passage 52 in the radialdirection Dr are closed by the nozzle head 33.

The processing liquids supplied to the respective upstream flow passages48A to 48D are supplied to the interior of the collective flow passage52. The width W1 of the slit discharge port 34 is narrow and therefore aportion of the processing liquid supplied to the downstream end 48 d ofeach of the upstream flow passages 48A to 48D spreads in thelongitudinal direction within the collective flow passage 52 beforearriving at the slit discharge port 34 while the remaining portion ofthe processing liquid is discharged from the slit discharge port 34without spreading in the longitudinal direction of the slit dischargeport 34 within the collective flow passage 52. A portion of theprocessing liquid supplied to a certain upstream flow passage 48 is thusmixed with the processing liquid supplied to another upstream flowpassage 48 in the interior of the collective passage 52 or in a spacebetween the substrate W and the slit discharge port 34. The processingliquids are thereby supplied to an entirety or substantially an entiretyof the slit discharge port 34 and a band-shaped liquid film extending inthe radial direction Dr is formed between the slit discharge port 34 andthe substrate W.

The processing liquid supplying system shall now be described in detailwith reference to FIG. 21 and FIG. 22.

The processing liquid supplying system includes the chemical liquid tank41 storing the chemical liquid, the chemical liquid flow passage 42guiding the chemical liquid fed from chemical liquid tank 41, theupstream heater 43 heating the chemical liquid flowing inside thechemical liquid flow passage 42 at the upstream temperature higher thanroom temperature (for example, of 20 to 30° C.) to adjust thetemperature of the chemical liquid inside the chemical liquid tank 41,the pump 44 feeding the chemical liquid inside the chemical liquid tank41 to the chemical liquid flow passage 42, and the circulation flowpassage 40 returning the chemical liquid inside the chemical liquid flowpassage 42 to the chemical liquid tank 41.

The processing liquid supplying system includes the supply valve 45 thatopens and closes the chemical liquid flow passage 42, the circulationvalve 46 that opens and closes the circulation flow passage 40, and thesupply flow passage 47 connected to the chemical liquid flow passage 42.An upstream switching unit includes the supply valve 45.

The processing liquid supplying system includes the plurality ofupstream flow passages 48 guiding the chemical liquid supplied from thesupply flow passage 47 toward the slit discharge port 34 and thecollective flow passage 52 supplying the chemical liquids supplied fromthe plurality of upstream flow passages 48 to the slit discharge port34. The processing liquid supplying system further includes theplurality of flowmeters 49 detecting flow rates of the liquids flowinginside the plurality of upstream flow passages 48, the plurality of flowcontrol valves 50 that change the flow rates of the liquids flowinginside the plurality of upstream flow passages 48, and the plurality ofdischarge valves 51 respectively opening and closing the plurality ofupstream flow passages 48. Although unillustrated, each flow controlvalve 50 includes the main valve body that opens and closes the flowpassage and the actuator that changes the open degree of the main valvebody. The actuator may be a pneumatic actuator or an electric actuatoror an actuator besides these.

The processing liquid supplying system includes the plurality ofdownstream heaters 53 that heat the chemical liquids flowing inside theplurality of upstream flow passages 48 besides the first upstream flowpassage 48A at downstream temperatures higher than the upstreamtemperature. The processing liquid supplying system further includes theplurality of return flow passages 54, respectively connected to theplurality of upstream flow passages 48 besides the first upstream flowpassage 48A at positions further downstream than the plurality ofdownstream heaters 53, and the plurality of return valves 55,respectively opening and closing the plurality of return flow passages54. A downstream switching unit includes the plurality of dischargevalves 51 and the plurality of return valves 55.

The processing liquid supplying system includes the cooler 56 coolingthe chemical liquids supplied from the plurality of return flow passages54 and the tank recovery flow passage 57 guiding the chemical liquidfrom the cooler 56 to the chemical liquid tank 41. The chemical liquidssupplied from the plurality of return flow passage 54 to the cooler 56are made closer in temperature to the upstream temperature by the cooler56 and thereafter guided via the tank recovery flow passage 57 to thechemical liquid tank 41. The cooler 56 may be a water cooled unit or anair cooled unit or may be a cooling unit other than these.

The processing liquid supplying system in a discharging state in whichthe chemical liquids are discharged from the slit discharge port 34shall now be described with reference to FIG. 21. In FIG. 21, an openvalve is indicated in black and a closed valve is indicated in white.

The chemical liquid inside the chemical liquid tank 41 is fed to thechemical liquid flow passage 42 by the pump 44. The chemical liquid fedby the pump 44 is heated by the upstream heater 43 and thereafter flowsfrom the chemical liquid flow passage 42 to the supply flow passage 47and flows to the plurality of upstream flow passages 48 from the supplyflow passage 47. The chemical liquids supplied to the plurality ofupstream flow passages 48 are supplied from the plurality of upstreamflow passages 48 to the slit discharge port 34 via the collective flowpassage 52. The chemical liquids supplied to the plurality of upstreamflow passages 48 are thereby discharged from the slit discharge port 34toward the upper surface of the substrate W.

Before being supplied to the slit discharge port 34, the chemicalliquids supplied to the plurality of upstream flow passages 48 besidesthe first upstream flow passage 48A are heated by the downstream heaters53. The temperatures (downstream temperatures) of heating of theprocessing liquids by the downstream heaters 53 are higher than thetemperature (upstream temperature) of heating of the processing liquidby the upstream heater 43. The second to fourth downstream temperaturesincrease in the order of the second to the fourth downstreamtemperatures. The temperatures of the chemical liquids supplied to thedownstream ends 48 d (see FIG. 25) of the first upstream flow passage48A to the fourth upstream flow passage 48D thus increase stepwise inthe order of the first upstream flow passage 48A to the fourth upstreamflow passage 48D.

The processing liquid supplying system in a discharge stoppage state inwhich the discharges of chemical liquids from the slit discharge port 34are stopped shall now be described with reference to FIG. 22. In FIG.22, an open valve is indicated in black and a closed valve is indicatedin white.

The chemical liquid inside the chemical liquid tank 41 is fed to thechemical liquid flow passage 42 by the pump 44. A portion of thechemical liquid fed by the pump 44 is heated by the upstream heater 43and thereafter returned to the chemical liquid tank 41 via thecirculation flow passage 40. The remaining portion of the chemicalliquid fed by the pump 44 flows from the chemical liquid flow passage 42to the supply flow passage 47 and flows from the supply flow passage 47to the plurality of upstream flow passages 48 besides the first upstreamflow passage 48A.

The chemical liquid inside the second upstream flow passage 48 is heatedby the downstream heater 53 associated with the second upstream flowpassage 48B and thereafter flows via the return flow passage 54 to thecooler 56. The same as the second upstream flow passage 48B applies tothe third upstream flow passage 48C and the fourth upstream flow passage48D. The chemical liquids supplied to the cooler 56 are cooled by thecooler 56 and return to the chemical liquid tank 41 via the tankrecovery flow passage 57. All of the chemical liquid fed to the chemicalliquid flow passage 42 by the pump 44 is thereby returned to thechemical liquid tank 41.

The temperature of the processing liquid may have, a large influence onthe processing of the substrate W. If the downstream heaters 53 arestopped during discharge stoppage, it will take time for thetemperatures of the processing liquids, heated by the downstream heaters53, to stabilize at the intended temperatures when operation of thedownstream heaters 53 is restarted. The discharge of processing liquidthus cannot be restarted immediately and throughput decreases.

As described above, even during discharge stoppage, the chemical liquidsare made to continue to flow to the downstream heaters 53 and thedownstream heaters 53 are made to heat the chemical liquids. A statewhere the temperatures of the downstream heaters 53 are stable can thusbe maintained. Further, the chemical liquids heated by the downstreamheaters 53 are returned to the chemical liquid tank 41 and theconsumption amount of the chemical liquid can thus be reduced. Moreover,the chemical liquid that is cooled by the cooler 56 is returned to thechemical liquid tank 41 and therefore variation of temperature of thechemical liquid inside the chemical liquid tank 41 can be suppressed.

An example of processing of the substrate W executed by the substrateprocessing apparatus 1 shall now be described. The respective operationsdescribed below are executed by the controller 3 controlling thesubstrate processing apparatus 1. FIG. 23 and FIG. 24 shall bereferenced in the following description. FIG. 7 shall be referencedwhere suitable.

When the substrate W is to be processed by the processing unit 2, thesubstrate W is carried into the interior of the chamber 7 by the hand(not shown) of the transfer robot in a state where the plurality ofnozzles 26 are retracted from above the spin chuck 11 and the splashguard 17 is positioned at the lower position. The substrate W is therebyplaced, in the state where the front surface is faced up, on theplurality of chuck pins 13. Thereafter, the hand of the transfer robotis retracted from the interior of the chamber 7 and thecarry-in/carry-out port 8 a of the chamber 7 is closed by the shutter 9.

After the substrate W has been placed on the plurality of chuck pins 13,the plurality of chuck pins 13 are pressed against peripheral edgeportions of the substrate W and the substrate W is gripped by theplurality of chuck pins 13. Also, the guard raising/lowering unit 18moves the splash guard 17 from the lower position to the upper position.The upper end of the splash guard 17 is thereby disposed higher than thesubstrate W. Thereafter, the spin motor 14 is driven to start rotationof the substrate W. The substrate W is thereby rotated at apredetermined liquid processing speed (of, for example, several hundredrpm).

Thereafter, the nozzle moving unit 24 moves the plurality of nozzles 26from the standby position to the processing position. The nozzle head 33are thereby overlapped with the substrate W in a plan view. Thereafter,the plurality of discharge valves 51, etc., are controlled and thechemical liquids are discharged at the same time from the plurality ofnozzles 26 (step S1 of FIG. 7). The plurality of nozzles 26 dischargethe chemical liquids in the state where the nozzle moving unit 24 keepsthe plurality of nozzles 26 still. When a predetermined time elapsesfrom the opening of the plurality of discharge valves 51, the dischargesof chemical liquids from the plurality of nozzles 26 are stopped at thesame time (step S2 of FIG. 7). Thereafter, the nozzle moving unit 24moves the plurality of nozzles 26 from the processing position to thestandby position.

The chemical liquids discharged from the plurality of nozzles 26 land atthe same time on a rectilinear region within the upper surface of thesubstrate W (see FIG. 27). The plurality of nozzles 26 discharge thechemical liquids toward the upper surface of the rotating substrate W. Arelative positional relationship of the substrate W and the rectilinearregion changes due to the rotation of the substrate W. The chemicalliquids are thereby made to land on the entire upper surface of thesubstrate W. The chemical liquids are thereby supplied to the entireupper surface of the substrate W and the liquid film of chemical liquidthat covers the entire upper surface of the substrate W is formed on thesubstrate W. The entire upper surface of the substrate W is therebyprocessed by the chemical liquid. Also, the chemical liquid on thesubstrate W is scattered to the periphery of the substrate W from theupper surface peripheral edge portion of the substrate W and received bythe inner peripheral surface of the splash guard 17.

After the discharges of chemical liquids from the plurality of nozzles26 have been stopped, the rinse liquid valve 23 is opened and dischargeof the rinse liquid (pure water) from the rinse liquid nozzle 21 isstarted (step S3 of FIG. 7). The chemical liquid on the substrate W isthereby rinsed off by the rinse liquid and the liquid film of the rinseliquid that covers the entire upper surface of the substrate W isformed. When a predetermined time elapses from the opening of the rinseliquid valve 23, the rinse liquid valve 23 is closed and the dischargeof the rinse liquid from the rinse liquid nozzle 21 is stopped (step S4of FIG. 7).

After the discharge of the rinse liquid from the rinse liquid nozzle 21has been stopped, the substrate W is accelerated in the rotationaldirection by the spin motor 14 and the substrate W is rotated at adrying speed (of, for example, several thousand rpm) higher than theliquid processing speed (step S5 of FIG. 7). The rinse liquid attachedto the substrate W is thereby spun off to the periphery of the substrateW and the substrate W is dried. When a predetermined time elapses fromthe start of high speed rotation of the substrate W, the rotation of thespin motor 14 and the substrate W is stopped.

After the rotation of the substrate W has been stopped, the guardraising/lowering unit 18 moves the splash guard 17 from the upperposition to the lower position. Further, the holding of the substrate Wby the plurality of chuck pins 13 is released. The transfer robot makesits hand enter the interior of the chamber 7 in the state where theplurality of nozzles 26 are retracted from above the spin chuck 11 andthe splash guard 17 is positioned at the lower position. Thereafter, thetransfer robot uses the hand to take the substrate W on the spin chuck11 and carries out the substrate W from the chamber 7.

FIG. 28 is a graph of etching amount distributions of substrates W.

The processing conditions of the substrates W of measurement A tomeasurement B shown in FIG. 28 are the same with the exception of thenozzles that discharge the chemical liquids.

The measurement A indicates the etching amount distribution when asubstrate W is etched by making the plurality of nozzles 26, from whichthe nozzle head 33 has been removed, discharge the chemical liquidswhile keeping still the plurality of nozzles 26. That is, themeasurement A indicates the etching amount distribution when the fourdischarge ports 34 (corresponding to the downstream ends 48 d of thefirst upstream flow passage 48A to the fourth upstream flow passage48D), respectively provided in the four main nozzle bodies 27, are madeto discharge the chemical liquids.

The measurement B indicates the etching amount distribution when just asingle discharge port (corresponding to the downstream end 48 d of thefirst upstream flow passage 48A) is made to discharge the chemicalliquid and the liquid landing position of the chemical liquid is fixedat the upper surface central portion of the substrate W.

With the measurement B, the etching amount decreases with distance awayfrom the central portion of the substrate W and the etching amountdistribution exhibits a peak-shaped curve. That is, the etching amountis greatest at the liquid landing position of the chemical liquid anddecreases with distance away from the liquid landing position. On theother hand, with the measurement A, the etching amounts at positionsbesides the central portion of the substrate W are increased and theetching uniformity is greatly improved in comparison to the measurementB.

With the measurement A, seven peaks are formed. The apex of the centralpeak is at a position corresponding to the innermost liquid landingposition and the apexes of the two peaks at outer sides thereof are atpositions corresponding to the second liquid landing position from theinner side. The positions of the apexes of the two peaks further to theouter sides are positions corresponding to the third liquid landingposition from the inner side, and the positions of the two outermostpeaks are positions corresponding to the fourth liquid landing positionfrom the inner side.

When chemical liquids are thus discharged toward the upper surface ofthe substrate W from a plurality of discharge ports that are aligned inthe radial direction Dr, the chemical liquids land on a plurality ofliquid landing positions that are separated in the radial direction Dr.The etching rate at a liquid landing position is higher than an etchingrate at a position between two adjacent liquid landing positions. Theprocessing uniformity is thus decreased. Such decrease of uniformity canthus be prevented by making the chemical liquids, discharged from theslit discharge port 34, land on the rectilinear region that iscontinuous in the radial direction Dr.

As described above, with the present preferred embodiment, theprocessing liquid is supplied from the supply flow passage 47 to allupstream flow passages 48 and supplied from all upstream flow passages48 to the collective flow passage 52. The processing liquids supplied tothe collective flow passage 52 are discharged from the slit dischargeport toward the upper surface of the substrate W. The band-shaped liquidfilm extending in the radial direction Dr between the upper surfacecentral portion of the substrate W and the upper surface peripheral edgeportion of the substrate W is thereby formed between the slit dischargeport 34 and the substrate W and lands on the rectilinear region withinthe upper surface of the substrate W. The processing uniformity can thusbe increased in comparison to a case of making the processing liquids bedischarged from a plurality of discharge ports aligned in the radialdirection Dr.

Also, the temperatures of the processing liquids supplied to thedownstream ends 48 d of the first upstream flow passage 48A to thefourth upstream flow passage 48D increase with increase of distance fromthe rotational axis A1 to the downstream end 48 d. The processingliquids of the same or substantially the same temperatures as theprocessing liquids supplied to the plurality of downstream ends 48 dland on positions directly below the plurality of downstream ends 48 d.On the other hand, a mixed liquid of processing liquids, supplied to twoof the plurality of downstream ends 48 d that are adjacent to eachother, lands at each position between the directly-below positions. Thatis, processing liquids that mutually differ in temperature are suppliedto two of the plurality of downstream ends 48 d that are adjacent toeach other, and a processing liquid of a temperature between the twotemperatures lands on a position between the directly-below positions.

The temperature of the processing liquid at each position of the slitdischarge port 34 thus increases stepwise or continuously with distancefrom the rotational axis A1 and the temperature uniformity of theprocessing liquid on the substrate W can thus be increased in comparisonto a case where a processing liquid of uniform temperature is dischargedfrom the slit discharge port 34. The processing uniformity can therebybe increased further. Therefore in comparison to a case where aprocessing liquid is made to land on just the upper surface centralportion of the substrate W, the processing uniformity can be increasedwhile reducing the consumption amount of the processing liquid suppliedto the substrate W.

Also with the present preferred embodiment, the slit discharge port 34overlaps, in a plan view, with the upper surface central portion and theupper surface peripheral edge portion of the substrate W. The processingliquids discharged from the slit discharge port 34 land at the same timeon the rectilinear region that includes the upper surface centralportion and the upper surface peripheral edge portion of the substrateW. The slit discharge port 34 discharges the processing liquids towardthe upper surface of the rotating substrate W. The relative positionalrelationship of the substrate W and the rectilinear region changes dueto the rotation of the substrate W. The processing liquids are therebymade to land on the entire upper surface of the substrate W and theprocessing uniformity can thus be increased.

Also with the present preferred embodiment, the width W1 of the slitdischarge port 34 is narrow and therefore a portion of the processingliquid supplied to an upstream flow passage 48 spreads in thelongitudinal direction within the collective flow passage 52 beforearriving at the slit discharge port 34 while the remaining portion ofthe processing liquid supplied to the upstream flow passage 48 arrivesat the slit discharge port 34 without spreading in the longitudinaldirection of the slit discharge port 34 within the collective flowpassage 52. A portion of the processing liquid is thus mixed with theprocessing liquid supplied to another upstream flow passage 48 in theinterior of the collective passage 52 or in the space between thesubstrate W and the slit discharge port 34. The temperatures of theprocessing liquids supplied to the substrate W can thereby be increasedstepwise or continuously with distance away from the rotational axis A1.

Also with the present preferred embodiment, the tips 28 a of theplurality of arm portions 28 are aligned in a plan view in the radialdirection Dr (see FIG. 24). When the plurality of nozzles 26 of the samelength are aligned in the horizontal direction orthogonal to thelongitudinal direction D1 so that the tips 28 a of the plurality of armportions 28 are aligned in a plan view in the radial direction Dr, theentirety of the plurality of nozzles 26 increases in width (see FIG. 9).When the plurality of nozzles 26 of different lengths are aligned in thevertical direction so that the tips 28 a of the plurality of armportions 28 are aligned in a plan view in the radial direction Dr, theentirety of the plurality of nozzles 26 increases in height (see FIG.29A and FIG. 29B).

On the other hand, with the present preferred embodiment, the pluralityof arm portions 28 are aligned in the horizontal alignment direction D2orthogonal to the longitudinal direction D1. Further, the tips 28 a ofthe plurality of arm portions 28 are shifted in the longitudinaldirection D1 such that, in regard to the longitudinal direction D1, thetips 28 a of the plurality of arm portions 28 are aligned in the orderof the first nozzle 26A to the fourth nozzle 26D from the rotationalaxis A1 side (see FIG. 24). The tips 28 a of the first nozzle 26A to thefourth nozzle 26D can thereby be aligned in the radial direction Dr in aplan view while suppressing both the width and the height of theentirety of the plurality of nozzles 26.

Also with the present preferred embodiment, the upstream ends of theplurality of upstream flow passages 48 are disposed inside the fluid box5. The supply flow passage 47 branches into the plurality of upstreamflow passages 48 inside the fluid box 5. Each upstream flow passage 48can thus be reduced in length (length in the direction in which theliquid flows) in comparison to a case where the supply flow passage 47branches into the plurality of upstream flow passages 48 at a positionfurther upstream than the fluid box 5. Temperature decrease of theprocessing liquid due to heat transfer from the processing liquid toeach upstream flow passage 48 can thereby be suppressed.

The present invention is not restricted to the content of the preferredembodiment and various modifications are possible within the scope ofthe present invention.

For example, although with the preferred embodiment described above, thecase where the number of the nozzles 26 is four was described, thenumber of the nozzles 26 may be two or three or may be five or more.

Although with the preferred embodiment, the case where the slitdischarge port 34 discharges the processing liquids in the dischargedirection perpendicular to the upper surface of the substrate W wasdescribed, the slit discharge port 34 may discharge the processingliquids in a discharge direction that is obliquely inclined with respectto the upper surface of the substrate W.

Although with the preferred embodiment, the case where the width W1 ofthe slit discharge port 34 is fixed was described, the width W1 of theslit discharge port 34 does not have to be fixed. For example, the widthW1 of the slit discharge port 34 increases stepwise or continuously withdistance away from the rotational axis A1.

Although with the preferred embodiment, the case where the nozzle head33 is connected to all nozzles (first nozzle 26A to fourth nozzle 26D)was described, one or two of the four nozzles do not have to beconnected to the nozzle head 33. For example, the nozzle head 33 may beconnected to just the second nozzle 26B to the fourth nozzle 26D asshown in FIG. 30. In this case, the processing liquid supplied to thefirst nozzle 26A is discharged toward the upper surface central portionof the substrate W from the downstream end 48 d of the first upstreamflow passage 48A.

Although with the preferred embodiment, the case where the chemicalliquid flowing through each of the return flow passages 54 toward thechemical tank 41 is cooled by the cooler 56 was described, the cooler 56may be omitted.

The controller 3 may decrease the flow rate of the processing liquidsupplied from the supply flow passage 47 to the plurality of upstreamflow passages 48 in the discharge stoppage state in comparison to theflow rate of the processing liquid supplied from the supply flow passage47 to the plurality of upstream flow passages 48 in the dischargingstate. In this case, the flow rate of the chemical liquids returningfrom the return flow passages 54 to the chemical liquid tank 41decreases during discharge stoppage, so that a heat amount applied tothe chemical liquid inside the chemical liquid tank 41 can be reducedand variation of liquid temperature can be suppressed.

Although with the preferred embodiment, the case where, during dischargestoppage, the liquids heated by the downstream heaters 53 are made toflow from the upstream flow passages 48 to the return flow passages 54was described, if the downstream heaters 53 are to be stopped duringdischarge stoppage, the return flow passages 54 may be omitted.

Although with the preferred embodiment, the case where a downstreamheater 53 is not disposed at the first upstream flow passage 48A whiledownstream heaters 53 are disposed at all upstream flow passages 48besides the first upstream flow passage 48A was described, thedownstream heaters 53 may be disposed at all upstream flow passages 48including the first upstream flow passage 48A.

Although with the preferred embodiment, the case where the plurality ofnozzles 26 are made to discharge the chemical liquids while keeping theplurality of nozzles 26 still was described, the plurality of nozzles 26may be made to discharge the chemical liquids while making the pluralityof nozzles 26 pivot around the nozzle pivoting axis A2.

Although with the preferred embodiment, the case where the chemicalliquid flow passage 42 that supplies the chemical liquid to the supplyflow passage 47 is provided was described, a plurality of processingliquid flow passages that supply liquids to the supply flow passage 47may be provided.

For example, a first liquid may be supplied from a first liquid flowpassage to the supply flow passage 47 and a second liquid may besupplied from a second liquid flow passage to the supply flow passage47. In this case, the first liquid and the second liquid are mixed inthe supply flow passage 47 and therefore a mixed liquid containing thefirst liquid and the second liquid is supplied from the supply flowpassage 47 to the plurality of upstream flow passages 48. The firstliquid and the second liquid may be liquids of the same type or may beliquids of different types. Specific examples of the first liquid andthe second liquid include a combination of sulfuric acid and hydrogenperoxide water and a combination of TMAH and pure water.

The controller 3 may control the temperatures of the processing liquidssupplied to respective portions of the front surface of the substrate Win accordance with a thickness of a thin film before processing to makeuniform the thickness of the thin film after processing.

FIG. 14 is a graph showing a conceptual image of the thickness of a thinfilm before and after processing and the temperature of a processingliquid supplied to a substrate W. The alternate long and short dashesline in FIG. 14 indicates the film thickness before processing and thealternate long and two short dashes line in FIG. 14 indicates the filmthickness after processing. The solid line in FIG. 14 indicates thetemperatures of the processing liquids supplied to the substrate W. Theabscissa axis of FIG. 14 indicates the radius of the substrate W. Thefilm thickness before processing may be input into the substrateprocessing apparatus 1 from an apparatus (for example, a host computer)other than the substrate processing apparatus 1 or may be measured by ameasuring instrument provided in the substrate processing apparatus 1.

With the example shown in FIG. 14, the controller 3 may control thesubstrate processing apparatus 1 so that the temperatures of theprocessing liquids vary similarly to the film thickness beforeprocessing. Specifically, the controller 3 may control the plurality ofdownstream heaters 53 so that the temperatures of the processing liquidsin the plurality of upstream flow passages 48 are temperatures that arein accordance with the film thickness before processing.

In this case, processing liquid of relatively high temperature issupplied to a position at which the film thickness before processing isrelatively large and processing liquid of relatively low temperature issupplied to a position at which the film thickness before processing isrelatively small. The etching amount of the thin film formed on thefront surface of the substrate W increases relatively at a position atwhich processing liquid of high temperature is supplied and decreasesrelatively at a position at which processing liquid of low temperatureis supplied. The thin film is thus made uniform in thickness afterprocessing.

Two or more of any of the arrangements described above may be combined.Two or more of any of the processes described above may be combined.

A feature of a certain preferred embodiment may be added to anotherpreferred embodiment.

The present application corresponds to Japanese Patent Application Nos.2015-029843, 2015-035519, 2015-035520, 2015-035521 and 2015-064802respectively filed on Feb. 18, 2015, Feb. 25, 2015, Feb. 25, 2015, Feb.25, 2015 and Mar. 26, 2015 in the Japan Patent Office, and the entiredisclosures of these applications are incorporated herein by reference.

While preferred embodiments of the present invention have been describedabove, it is to be understood that variations and modifications will beapparent to those skilled in the art without departing the scope andspirit of the present invention. The scope of the present invention,therefore, is to be determined solely by the following claims.

What is claimed is:
 1. A substrate processing apparatus comprising: asubstrate holding unit rotating a substrate around a vertical rotationalaxis passing through a central portion of the substrate while holdingthe substrate horizontally; and a processing liquid supplying systemincluding an upstream heater, a supply flow passage, a plurality ofupstream flow passages, a plurality of downstream flow passages, aplurality of discharge ports and a plurality of downstream heaters andsupplying a processing liquid to the substrate held by the substrateholding unit; and wherein the upstream heater heats the processingliquid to be supplied to the supply flow passage, the supply flowpassage guides the processing liquid toward the plurality of upstreamflow passages, the plurality of upstream flow passages branch from thesupply flow passage and guide the processing liquid, supplied from thesupply flow passage, toward the plurality of discharge ports, theplurality of discharge ports include a main discharge port, dischargingthe processing liquid toward an upper surface central portion of thesubstrate, and a plurality of auxiliary discharge ports, disposed awayfrom the upper surface central portion, differing in distance from therotational axis, and respectively discharging the processing liquidtoward a plurality of positions within an upper surface of thesubstrate, and are respectively disposed at a plurality of positionsdiffering in distance from the rotational axis and discharge theprocessing liquid, supplied via the plurality of upstream flow passages,toward the upper surface of the substrate held by the substrate holdingunit, the plurality of upstream flow passages include a main upstreamflow passage connected to the main discharge port and a plurality ofauxiliary upstream flow passages connected to the plurality of auxiliarydischarge ports via the plurality of downstream flow passages, theplurality of downstream heaters are respectively connected to theplurality of auxiliary upstream flow passages and heat the processingliquid flowing through the plurality of auxiliary upstream flow passagesand each of the plurality of auxiliary upstream flow passages is abranching upstream flow passage that branches into a plurality of thedownstream flow passages and each auxiliary discharge port isrespectively provided according to each downstream flow passage, whereinthe plurality of discharge ports include an innermost discharge portthat overlaps with the central portion of the substrate in a plan viewand an outermost discharge port that overlaps with a peripheral edgeportion of the substrate in a plan view.
 2. The substrate processingapparatus according to claim 1, wherein the processing liquid supplyingsystem further includes a plurality of return flow passages and adownstream switching unit, the plurality of return flow passages arerespectively connected to the plurality of auxiliary upstream flowpassages at positions further upstream than the plurality of auxiliarydischarge ports, the plurality of downstream heaters are respectivelyconnected to the plurality of auxiliary upstream flow passages atpositions further upstream than the connection positions of the returnflow passages and the auxiliary upstream flow passages and heat liquidsflowing through the plurality of auxiliary upstream flow passages, andthe downstream switching unit switches to any of a plurality of statesincluding a discharging state, in which the liquid supplied to theplurality of upstream flow passages from the supply flow passage issupplied to the plurality of discharge ports, and a discharge stoppagestate, in which the liquid supplied to the plurality of upstream flowpassages from the supply flow passage is supplied to the plurality ofreturn flow passages.
 3. The substrate processing apparatus according toclaim 1, wherein the substrate processing apparatus further comprises: achamber housing the substrate held by the substrate holding unit; andthe branching upstream flow passages branch into the plurality ofdownstream flow passages inside the chamber.
 4. The substrate processingapparatus according to claim 1, wherein the plurality of discharge portsinclude an oblique discharge port that discharges the processing liquidin a discharge direction that is inclined with respect to the uppersurface of the substrate so as to approach the rotational axis as theupper surface of the substrate is approached.
 5. The substrateprocessing apparatus according to claim 1, wherein the substrateprocessing apparatus further comprises: a controller controlling theprocessing liquid supplying system; the processing liquid supplyingsystem further includes a plurality of discharge valves, the pluralityof discharge ports include a first discharge port and a second dischargeport disposed further from the rotational axis than the first dischargeport, the plurality of upstream flow passages include a first upstreamflow passage guiding the processing liquid toward the first dischargeport and a second upstream flow passage guiding the processing liquidtoward the second discharge port, the plurality of discharge valvesinclude a first discharge valve opening and closing the first upstreamflow passage and a second discharge valve opening and closing the secondupstream flow passage, and the controller opens the first dischargevalve and the second discharge valve such that a time during which thesecond discharge valve is open is longer than a time during which thefirst discharge valve is open and thereafter closes the first dischargevalve and the second discharge valve.
 6. A substrate processingapparatus comprising: a substrate holding unit rotating a substratearound a vertical rotational axis passing through a central portion ofthe substrate while holding the substrate horizontally; and a processingliquid supplying system including an upstream heater, a supply flowpassage, a plurality of upstream flow passages, a plurality ofdownstream flow passages, a plurality of discharge ports, a plurality ofdownstream heaters, a first nozzle and a second nozzle, and supplying aprocessing liquid to the substrate held by the substrate holding unit;and wherein the upstream heater heats the processing liquid to besupplied to the supply flow passage, the supply flow passage guides theprocessing liquid toward the plurality of upstream flow passages, theplurality of upstream flow passages branch from the supply flow passageand guide the processing liquid, supplied from the supply flow passage,toward the plurality of discharge ports, the plurality of dischargeports include a main discharge port, discharging the processing liquidtoward an upper surface central portion of the substrate, and aplurality of auxiliary discharge ports, disposed away from the uppersurface central portion, differing in distance from the rotational axis,and respectively discharging the processing liquid toward a plurality ofpositions within an upper surface of the substrate, and are respectivelydisposed at a plurality of positions differing in distance from therotational axis and discharge the processing liquid, supplied via theplurality of upstream flow passages, toward the upper surface of thesubstrate held by the substrate holding unit, the plurality of upstreamflow passages include a main upstream flow passage connected to the maindischarge port and a plurality of auxiliary upstream flow passagesconnected to the plurality of auxiliary discharge ports via theplurality of downstream flow passages, the plurality of downstreamheaters are respectively connected to the plurality of auxiliaryupstream flow passages and heat the processing liquid flowing throughthe plurality of auxiliary upstream flow passages, each of the pluralityof auxiliary upstream flow passages is a branching upstream flow passagethat branches into a plurality of the downstream flow passages and eachauxiliary discharge port is respectively provided according to eachdownstream flow passage, the plurality of discharge ports include afirst discharge port, disposed in the first nozzle, and a seconddischarge port, disposed in the second nozzle, and are aligned in a planview in a radial direction orthogonal to the rotational axis, the firstnozzle includes a first arm portion extending in a horizontallongitudinal direction and a first tip portion extending downward from atip of the first arm portion, the second nozzle includes a second armportion extending in the longitudinal direction and a second tip portionextending downward from a tip of the second arm portion, the first armportion and the second arm portion are aligned in a horizontal alignmentdirection orthogonal to the longitudinal direction, and the tip of thefirst arm portion and the tip of the second arm portion are separated inthe longitudinal direction in a plan view such that the tip of the firstarm portion is positioned at the rotational axis side.
 7. A substrateprocessing apparatus comprising: a substrate holding unit rotating asubstrate around a vertical rotational axis passing through a centralportion of the substrate while holding the substrate horizontally; and aprocessing liquid supplying system including an upstream heater, asupply flow passage, a plurality of upstream flow passages, a pluralityof downstream flow passages, a plurality of discharge ports, a pluralityof downstream heaters, a nozzle rotator and a discharge positionadjuster disposed on the nozzle rotator, and supplying a processingliquid to the substrate held by the substrate holding unit; and whereinthe upstream heater heats the processing liquid to be supplied to thesupply flow passage, the supply flow passage guides the processingliquid toward the plurality of upstream flow passages, the plurality ofupstream flow passages branch from the supply flow passage and guide theprocessing liquid, supplied from the supply flow passage, toward theplurality of discharge ports, the plurality of discharge ports include amain discharge port, discharging the processing liquid toward an uppersurface central portion of the substrate, and a plurality of auxiliarydischarge ports, disposed away from the upper surface central portion,differing in distance from the rotational axis, and respectivelydischarging the processing liquid toward a plurality of positions withinan upper surface of the substrate, and are respectively disposed at aplurality of positions differing in distance from the rotational axisand discharge the processing liquid, supplied via the plurality ofupstream flow passages, toward the upper surface of the substrate heldby the substrate holding unit, the plurality of upstream flow passagesinclude a main upstream flow passage connected to the main dischargeport and a plurality of auxiliary upstream flow passages connected tothe plurality of auxiliary discharge ports via the plurality ofdownstream flow passages, the plurality of downstream heaters arerespectively connected to the plurality of auxiliary upstream flowpassages and heat the processing liquid flowing through the plurality ofauxiliary upstream flow passages, each of the plurality of auxiliaryupstream flow passages is a branching upstream flow passage thatbranches into a plurality of the downstream flow passages and eachauxiliary discharge port is respectively provided according to eachdownstream flow passage, the nozzle rotator moves the plurality ofdischarge ports and the discharge position adjuster horizontally about apivoting axis between a processing position, at which the plurality ofdischarge ports and the substrate overlap in a plan view, and a standbyposition, at which the plurality of discharge ports and the substrate donot overlap in a plan view, and the discharge position adjuster movesthe plurality of discharge ports linearly in a horizontal adjustingdirection differing from a rotational direction of movement of theplurality of discharge ports by the nozzle rotator.
 8. A substrateprocessing apparatus comprising: a substrate holding unit rotating asubstrate around a vertical rotational axis passing through a centralportion of the substrate while holding the substrate horizontally; and aprocessing liquid supplying system including an upstream heater, asupply flow passage, a plurality of upstream flow passages, a pluralityof downstream flow passages, a plurality of discharge ports, a pluralityof downstream heaters and a nozzle, and supplying a processing liquid tothe substrate held by the substrate holding unit; and wherein theupstream heater heats the processing liquid to be supplied to the supplyflow passage, the supply flow passage guides the processing liquidtoward the plurality of upstream flow passages, the plurality ofupstream flow passages branch from the supply flow passage and guide theprocessing liquid, supplied from the supply flow passage, toward theplurality of discharge ports, the plurality of discharge ports include amain discharge port, discharging the processing liquid toward an uppersurface central portion of the substrate, and a plurality of auxiliarydischarge ports, disposed away from the upper surface central portion,differing in distance from the rotational axis, and respectivelydischarging the processing liquid toward a plurality of positions withinan upper surface of the substrate, and are respectively disposed at aplurality of positions differing in distance from the rotational axisand discharge the processing liquid, supplied via the plurality ofupstream flow passages, toward the upper surface of the substrate heldby the substrate holding unit, the plurality of upstream flow passagesinclude a main upstream flow passage connected to the main dischargeport and a plurality of auxiliary upstream flow passages connected tothe plurality of auxiliary discharge ports via the plurality ofdownstream flow passages, the plurality of downstream heaters arerespectively connected to the plurality of auxiliary upstream flowpassages and heat the processing liquid flowing through the plurality ofauxiliary upstream flow passages, each of the plurality of auxiliaryupstream flow passages is a branching upstream flow passage thatbranches into a plurality of the downstream flow passages and eachauxiliary discharge port is respectively provided according to eachdownstream flow passage, the plurality of discharge ports include aplurality of discharge ports provided in the nozzle, the nozzle includesan arm portion extending in a horizontal longitudinal direction and atip portion extending downward from the arm portion and a nozzle headmounted on the tip portion, and the branching upstream flow passagebranches into the plurality of the downstream flow passages inside thenozzle head.